Machine for machining large parts

Machine for machining large parts of the type that comprises a parallel kinematics machining device that moves freely in the X, Y and Z Cartesian axes, characterized in that the said device is mounted on a platform which moves in the Z axis and is in turn mounted on a bridge that slides along corresponding guides in the X and Y axes. The invention put forward affords the significant advantage of combining the high machining precision and speed of the parallel kinematics machine with the fact that the machine can access large work areas owing to the support platform which is mounted on the bridge.

1. A machine for machining large parts, comprising: a pair of spaced apart parallel first guides extending in an X Cartesian coordinate direction; a mobile bridge extending over the first guides in a Y Cartesian coordinate direction and mounted to the first guides for movement of mobile bridge in the X Cartesian coordinate direction; a pair of spaced apart parallel second guides connected on the mobile bridge and extending in a Y Cartesian coordinate direction; a platform mounted to the second guides on top of the bridge , for movement in the Y Cartesian coordinate direction; a parallel kinematics machine comprising a plurality of interpolated axes each with a lower end, and a head connected to a lower end of the interpolated axes for movement of the head by the interpolated axes, the parallel kinematics machine being mounted to the platform for movement in a Z Cartesian coordinate direction; and an actuator connected to the platform for moving the parallel kinematics machine in the Z Cartesian coordinate direction, so that the parallel kinematics machine is movable in all of the X, Y and Z orthogonal Cartesian coordinate directions.

2. A machine for machining large parts according to claim 1, including a computing control unit for synchronizing the X, Y and Z Cartesian coordinate direction movements of the bridge, and platform and the parallel kinematics machine.

The present descriptive memory refers, as its title indicates, to a machine for machining large parts, of the type that comprises of a bridge that slides along two guides and supports the machining device.

Currently there are several types of machines consisting of a bridge that slides along two guides and is fitted with the device or tool that will act on the part to be machined. These devices or tools are designed to move horizontally, transversely and vertically by means of the aforementioned bridge and the guides, in order to perform the machining tasks they are programmed for.

There are also multiple systems or devices for part machining, commonly known in the industry as parallel kinematics machines (PKM), which allow part machining in a predetermined confined space by means of multiple interpolated axes.

One of the disadvantages presented by machines comprising a bridge and its corresponding guides is that operating speeds and accelerations are low, and that very frequently wide machining tolerances are required due to the lack of resistance to bending caused by certain torsion phenomena.

As for the machines or devices for machining purposes based on the parallel kinematics system, it must be said that although they provide precision and high speed and acceleration, its application scope is limited and consequently this system is not currently used for large parts machining purposes.

To solve the problems currently affecting large parts machining, the machine that is the subject of the present invention has been developed. The machine, based on the three Cartesian axes system -X, Y and Z-, comprises a bridge whose feet slide horizontally -X- along two guides, a sliding platform, fitted on top of the bridge, that moves transversely -Y- in relation to the guides, and a parallel kinematics machine or device for machining purposes, of any of the common types known in the industry, anchored onto this platform. The parallel kinematics device anchored onto the bridge¡¯s platform moves upwards and downwards in the -Z- coordinate, activated by any commercial device, for example, actuator cylinders, perpetual screws, racks, etc.

The machine for machining parts put forward has multiple advantages over the solutions currently used in the industry. The most important one is that the working tool has access to wide work areas by virtue of its movements in coordinates X, Y and Z, plus the total flexibility of movements that the parallel kinematics head has within its own work area.

Another advantage of the present invention is the synchronization of the operation of the parallel kinematics machine with its movements in the X, Y and Z Cartesian axes; in other words, while the parallel kinematics machine works at full speed and acceleration, the Cartesian axes track its movement, making it possible to expand the PKM¡¯s work area to the whole Cartesian area of the machine presented here.

Another significant advantage of the machine put forward is its high resistance to bending, which allows a high degree of precision, since the absence of torsion phenomena allows minimum tolerances.

Another important advantage of the present invention is its high operating speed, which obviously significantly reduces machining times and therefore costs.

The final advantage of the machine for machining large parts we will mention is its low manufacturing cost compared to that of other sophisticated machines used in the industry.