Machine for producing spiral-toothed bevel gears

Abstract

A CNC machine for producing spiral-toothed bevel gears is described, which has a first carriage supporting a tool spindle and is displaceable in height, and whose guide is disposed on a lateral surface of a machine housing, which is horizontally guided in a straight coordinate axis on a machine base. The tool spindle axis is parallel with the lateral surface and with the coordinate axis. Furthermore, the machine has a workpiece spindle support having a second carriage and a pivoting device with a vertical axis and is also horizontally guided on the machine base. The parallel arrangement of the tool spindle axis results in a new machine concept with a compact structure and optimal chip flow. Therefore the machine is particularly suited for heavy-duty dry milling. Since the tool spindle is not located above the area of the machine having a horizontal guide, it is possible to arrange a chip collector underneath the tool spindle, which can be reached by the chips essentially under the force of gravity.

Description

.Iadd.This application is a substitute of reissue Ser. No. 09 / 538,859, now abandoned..Iaddend.FIELD OF THE INVENTIONThe invention relates to a machine for producing spiral-toothed bevel gears, in particular a CNC machine, with a first carriage which supports a tool spindle and is displaceable in height, whose guide is disposed on a lateral surface of a machine housing, which is horizontally guided in a straight coordinate axis on a machine base, wherein the tool spindle axis is parallel with the lateral surface, and with a workpiece spindle support having a second carriage and a pivoting device with a vertical axis, which is also horizontally guided on the machine base.BACKGROUND OF THE INVENTIONGear cutting machines for bevel gears, wherein the conventional generating cradle or generating drum has been replaced by a type of a compound carriage, are usually embodied in accordance with the following concept: a tool or cutter head spindle and its drive are located on a first carriage,...

AI Technical Summary

Benefits of technology

It is an object of the present invention to improve the design of a machine for producing spiral-toothed bevel gears, in particular a CNC machine, with a first carriage which supports a tool spindle and is displaceable in height, whose guide is disposed on a lateral surface of a machine housing, which is horizontally guided in a straight coordinate axis on a machine base, wherein the tool spindle axis is parallel with the lateral surface, and with a workpiece spindle support having a second carriage and a pivoting device with a vertical axis, which is also horizontally guided on the machine base, in such a way that it permits ergonomic operation, but no movement deviation.

Since with the machine in accordance with the invention the tool spindle axis is parallel with the lateral surface of the machine housing on which the first carriage is disposed, the operating elements of the machine can be arranged in such a way that an ergonomical operation is possible. It is possible in this case to arrange both carriages on the same side, viewed from the position of the operator, which allows a simple, safe and efficient operation of the machine. The mechanical structure of the machine in accordance with the invention is such that with manual feeding the workpiece is moved to the operator. Because of this the machine in accordance with the invention is also particularly ergonomic. No bending into the machine is required for changing a workpiece. Because of the arrangement in close proximity to the machine housing and the workpiece spindle support in the machine in accordance with the invention, the optimal distribution of the movements on the tool and workpiece sides is possible with an optimal flow of force, because of which a maximum process stiffness can be achieved. This is of importance, since with CNC machines the static stiffness of the machine must be as large as possible, the same as with mechanical machines. However, this is not the only determining parameter with CNC machines. Because of the control circuits which consist of an actuator (servo motor and machine element), controller (CNC and axis actuator) and a position sensor (measuring system), a much more complex technical control behavior results. This pertains in particular to the movement deviation which, in CNC machines, is a function of the static stiffness and the quality of the control circuits, besides an effective chip and heat removal. Static stiffness is optimally assured with the machine in accordance with the invention, since the arrangement of the operating elements makes short and very stiff drive trains possible. The close arrangement next to each other of the tool spindle support and the machine housing furthermore allows a very compact structure of the machine in accordance with the invention possible.

If in an embodiment of the invention the lateral surface is furthermore selected in such a way that the tool spindle is not located above an area of the machine including a horizontal guide of the workpiece spindle support or of the machine housing, into which chips could be introduced during the operation, no horizontal guides, which could become soiled by chips, are located in this area. This area of the machine can furthermore be used for other uses than guiding. A completely unhindered access to at least the first carriage of the machine is furthermore possible, which simplifies the maintenance of the carriage and the changing of the tools.

If a chip collector is arranged underneath the tool spindle, which the chips essentially reach under the effects of gravity, the chips can be caught in a simple manner and removed. In this case the machine base can be usefully recessed at least at the place where the chip collector will be arranged. Since, as explained above, the chips take 80% of the heat along with them during dry milling, heating of the machine base is also prevented by means of the chip collector. Therefore the requirement is met to provide for the fastest possible removal of the chips during dry milling and to prevent their contact with the machine base or other parts of the machine as much as possible.

If in a still further embodiment of the invention the first carriage has a guide in a further straight coordinate axis, the Z-axis, which is inclined in respect to the vertical direction, this represents an inclined base arrangement in which the base of the machine housing can be made particularly wide in the direction transversely to the tool spindle axis. This leads to an especially large machine stiffness. A more advantageous chip conveyance into the chip collector also results from the inclined base arrangement, which is advantageous particularly in connection with dry milling. In this embodiment the machine in accordance with the invention is conceived for an optimal chip flow. Since the essential portion of the heat generated in the course of dry milling is removed by means of the chips, the inclined base arrangement makes it possible in a particularly safe manner that the thermal influence of the chips is removed in that the chips are not even brought into contact with the machine base or other functional elements of the machine, but instead drop into the chip collector as soon as possible. Although this is also the case with other embodiments of the machine in accordance with the invention, the inclined base arrangement offers the best conditions. Thus, by means of the special conception of the inclined base arrangement, the machine is not only especially stiff, but also especially well suited for dry milling.

The compact side by side arrangement of the machine housing and the workpiece spindle support, which is made possible by the arrangement in accordance with the invention of the tool spindle axis, offers the further advantage that to prevent failing of chips, the machine can be completely encapsulated. It is possible to provide covers which are designed so they are inclined toward the chip collector and guide those generated chips, which do not directly fall into the chip collector, to it. It is furthermore possible to provide sheathing, in particular between the machine housing and the workpiece spindle support, which protects both the second carriage and the pivoting device from falling chips. A chip guide constructed in this way with the aid of guide surfaces on the cover and the sheathing makes the machine in accordance with the invention particularly well suited for heavy-duty dry milling. But these advantages are also fully realized if it is intended to perform wet-milling for reasons of technology.

Problems solved by technology

However, this is not the only determining parameter with CNC machines.

Because of the control circuits which consist of an actuator (servo motor and machine element), controller (CNC and axis actuator) and a position sensor (measuring system), a much more complex technical control behavior results.

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