Forming device and method for smoothing the surface of a workpiece

The object of the present invention is a forming device for smoothing the surface of a workpiece, intended especially for smoothing the surface of pieces of metal and objects of hard plastic. Another object of the invention is a method for smoothing the surface of a workpiece.

The aim of the present invention is to achieve a forming device and method by means of which the surface of a workpiece can be accurately and efficiently smoothed. To achieve this aim, the forming device according to the invention is characterised in that the forming device comprises a machining unit having a tool which sets against the surface of the workpiece, the tool being arranged to direct a hammering impact effect of essentially ultrasonic frequency at the surface of the workpiece, and means for feeding machining liquid to the area being machined. The method according to the invention is, for its part, characterised in that in the method, a hammering impact effect of essentially ultrasonic frequency is directed at the surface of the workpiece by means of a tool which sets against the surface of the workpiece.

The invention is described in greater detail in the following, with reference to the accompanying drawing, the single Figure 1 of which shows a diagrammatic view in principle of the components of the forming device.

The forming device according to the invention shown diagrammatically in Figure 1 as an exemplary implementation comprises a generator 6, which generates an ultrasonic electric current in it by means of three-phase alternating current supplied via a feed cable 10, the said electric current being conducted along cabling 11 to a machining unit 2. The machining unit acts as a converter which converts the electric current of ultrasonic frequency into mechanical movement conveyed to a tool 3 arranged in the converter 2. The tool 3 directs the hammering impact effect at the surface of the workpiece being processed, as a result of which the surface of the workpiece becomes smoother and harder. The converter 2 is in addition provided with machining liquid nozzles 4, by means of which a jet of machining liquid 5 delivered to the converter 2 from the machining liquid feed line 9, via a filter 8, is

led to the area being machined. The purpose of the machining liquid supplied to the converter is to cool the converter 2 and also to act as a lubricant in the forming process. The alternating current may also be one-phased. In the forming device is preferably also arranged a remote control 7 for controlling the forming device. In the converter 2 is preferably arranged a suspension mechanism (not shown) by means of which the machining force exerted by the tool 3 on the workpiece may be adjusted. The position of the tool 3 is preferably adjustable and it may be implemented in various forms, for example, there may be specific special tools for processing the inner surfaces of holes and/or for handling different materials. The tools are preferably made of a hard bit material, such as hard metals, ceramics and diamonds.

The converter is preferably provided with fastening means allowing fastening to a lathe, and it may be equipped, for example, with conical fastening means with which it may be fastened to a milling machine or machining centre or other corresponding machining device instead of a lathe.

In conjunction with the generator is preferably arranged an accessory box on wheels for storing the loose parts of the device. In it is also arranged a space for a separate cooling system which can be used, for example, when the machine tool's own cutting fluid circulation cannot be used for cooling.