Work holders – Holder mounted for movement – With plural means for changing holder positions
Reexamination Certificate
1999-03-19
2001-06-05
Banks, Derris H. (Department: 3723)
Work holders
Holder mounted for movement
With plural means for changing holder positions
C267S071000, C267S064260, C267S050000
Reexamination Certificate
active
06241229
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention is directed to a machine for the processing of plate-like workpieces, in particular sheet metal, which have a machine frame, a worktable, and a guidance system for moving the workpiece thereabout.
Generally, modern punch presses and like stamping machines have a work table and at least one processing station. A coordinate guide moves the workpiece over the work table parallel to the plane of the work table in two coordinate directions extending perpendicular to each other. This includes a guide rail mounted on the machine frame and movable in the one coordinate direction, and the rail carries at least one workpiece support movable in the other coordinate direction.
In German patent publication DE-A-22 64 852 a revolving punch press is shown in which a machine base with a work table has a guide rail upon which there is mounted a cross-sliding carriage holding the workpiece to be processed. This guide rail is movable in a coordinate direction parallel to the plane of the work table. The cross-sliding carriage at the same time is movable on the guide rail in its longitudinal direction and is consequently movable crosswise to the direction of the sliding of the guide rail. The guide rail and cross-sliding carriage form the coordinate guide of the previously known machine tool.
In its longitudinal direction the guide rail projects on both sides over the work table on the machine base. The fixed work table on the machine base together with two side tables which are movable with the guide rail and engaged with the overhangs of the guide rail to monide the workpiece support. Sliding guide carriages are used for guiding and supporting of the side tables on the machine base and these carriages are also attached to the guide rail and work together with corresponding guide implements on the machine base. The cross-sliding carriage is movable on the guide rail in its longitudinal direction and has clamps for the firm gripping of the sheet metal workpiece to be processed.
During practical implementation of the machines of the type known from German patent publication DE-A-22 64 852, undesired distortions and displacements of the guide rail have adversely occurred. These manifestations were in particular the result of the inertia of the masses being accelerated with the guide rail during machine operation, for example, the cross-sliding carriage mounted on the guide rail, the workpiece held to the guide rail over the cross-sliding carriage and/or of the side tables fastened to the guide rail including the elements for the guiding and supporting of the side tables on the machine base.
To avoid the described undesired distortions and displacements of the guide rail, machines are presently being used to form a unique type. For the reinforcement of the coordinate guide, machines are being supplied with reinforcing elements as seen in German patent publication DE-A-22 64 852. These elements support the guide rail on the machine frame against distortion and displacement in at least one plane running parallel to the plane of the work table. Supports that run between the overhangs of the guide rail and the machine frame and that are moved together with the guide rail come into use as reinforcing elements. The application of such supports then leads to an enlargement of the mass to be supported on the machine frame and to be accelerated together with the guide rail. This in turn requires an appropriate design of the machine frame with respect to its load-bearing capacity. The necessary reinforcement of the coordinate guide on the machines currently in use connect a relatively large mass and this is added to the relatively large weight of the coordinate guide and thereby the entire machine.
The present invention has aimed to enable an improvement in this regard.
SUMMARY OF THE INVENTION
In accordance with the present invention, the identified problem is solved by means of supplying a self-supporting plate as a reinforcing element on the machine which has a surface forming at least one part of the workpiece support. On machines in accordance with the invention, the self-supporting plate takes on a double function. Firstly, it is used for a reinforcement of the coordinate guide, in particular as a support of moment for the guide rail; secondly, it takes on the function of an indispensable workpiece support that augments the work table of the machine frame or a proportionate dimension of the workpiece to be processed. The advantage of the invention can be appreciated from the application of a separate component, serving exclusively for the reinforcement of the coordinate guide.
In the development of the invention, the self-supporting plate is supported and movable with the guide rail above a support bearing on the machine frame facing this bearing. Crosswise to its sliding direction the support provided by the support bearing is thoroughly free of play.
In the preferred design of the machine in accordance with the invention, the self-supporting plate is formed as a hollow chamber plate. The application of a hollow chamber plate as a workpiece support brings with it a considerable savings in weight with respect to the conventional side tables used as supplementary to the workpiece table of the machine frame.
In the interest of a maximal self-supporting stability with minimal mass as well as minimal weight in the case of a further preferred variant of the machine in accordance with the invention, it is intended that the self-supporting plate will exhibit an inner honeycomb structure with honeycomb partitions running in a crosswise direction to the plane of the plate.
A further design of the invention concerns a machine suitable to the type whose guide rail projects on both sides of the workpiece table with in each case an overhang facing the work table. On each of the overhangs of the guide rail is provided a workpiece support forming a workpiece contact in cooperation with the work table, and a reinforcing element is provided between each of the overhangs of the guide rail and the machine frame. In development of the invention in the interest of minimizing the mass that is to be moved with the guide rail, both reinforcing elements are formed as self-supporting plates and as providing a surface which is a part of the workpiece support.
In the following, the invention is explained more closely with the aid of schematic representations for an example of implementation.
REFERENCES:
patent: 2862410 (1958-12-01), Meyer
patent: 4392642 (1983-07-01), Chityat
patent: 4409860 (1983-10-01), Moriyama et al.
patent: 4565358 (1986-01-01), Hosoi et al.
patent: 4802567 (1989-02-01), Ikeda et al.
patent: 5022619 (1991-06-01), Mamada
patent: 5171002 (1992-12-01), Herke et al.
patent: 5207115 (1993-05-01), Takei
patent: 5388316 (1995-02-01), MacLaren
patent: 5752821 (1998-05-01), Jo
patent: 6017597 (2000-01-01), Minakami et al.
patent: 6047958 (2000-04-01), Marinkovic
patent: 20 49 237 (1972-04-01), None
patent: 31 09 862 (1982-10-01), None
patent: 32 08 989 (1983-09-01), None
patent: 33 39 340 (1984-05-01), None
Bundschu Stephan
Erlenmaier Werner
Laib Wolfgang
Banks Derris H.
Pepe & Hazard LLP
Trumpf GmbH & Co.
Wilson Lee
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