Automated machining of door and window fittings
Did you ever stop to consider that hinges and other
accessories for doors and windows are innovative products that are subject to a continuous process of refinement and enhancement? At Sobinco based in Zulte-Waregem, Belgium, FANUC machines, both electrical discharge (EDM) machines for prototyping and
milling machines and robots in production, operate at full capacity machining door and window fittings.
Modern
hinges for doors and windows contain a lot of sophisticated technology ensuring that they maintain the required tension and proper adjustment of the components. Appearance is an equally important factor – for example, the recent trend to concealed window hinges, which are both aesthetically attractive and offer maintenance advantages. Each year, the R&D division of the Belgian window and door fittings manufacturer Sobinco develops tests and prepares several dozen new models for production.
FANUC EDM machines for precision machining
A hinge consists of two parts which move in relation to each other via a hinge pin in a pivot. The hinge pin is located on a metal plate that is fixed to the door, window or post. The production of hinges starts with an extruded metal section in the form of a plate and a hinge pin; the workpieces are then drilled out and milled. The
first prototypes are cut from an aluminium block. For this purpose, Sobinco uses
FANUC EDM machines for machining door and window fittings to the desired precision and surface finish in a single action.
Drilling jigs and prototypes
Electrical erosion and electrical discharge machining door and window fittings in general is perhaps one of the least known technologies in the arsenal of the metal machinist, but Sobinco is one of many companies that is convinced of its potential and its advantages. Luc Cosyns is the head of Sobinco’s Tooling Dept. where the prototypes and jigs are created.
The company operates six ROBOCUT machines, three of which are new models of the
α-C400 iA type.
“For the prototypes, we start with a 200 mm block of aluminium. A section is cut out of the block.
A 0.25 mm wire is drawn across an initial opening with a jet of water. The machine applies a voltage between the wire and the workpiece which generates discharges which erode the material. In this way the wire cuts a contour.”
Before taking charge of jig production, Luc worked for many years with EDM machines, a technology in which accordingly he is extremely well versed and from which he knows how to obtain the best results. He can for example
create gears with oblique teeth on a ROBOCUT in a single operation, by placing the wire diagonally via the CNC controller. For Sobinco, one of
the big advantages of ROBOCUT is its reliability. Luc Cosyns: “The operator prepares the work on a CAO/FAO system. Once the machine is started, we expect it to
machine the workpiece without supervision so that the workpiece is ready next morning."