MXPA00005579A

MXPA00005579A - Device for fastening a tool on a driveable tool spindle of a machine tool in a progressively adjustable manner

Info

Publication number: MXPA00005579A
Application number: MXPA/A/2000/005579A
Authority: MX
Inventors: Guido Kochsiek
Original assignee: Iprotec Maschinen Und Edelstahlprodukte Gmbh
Priority date: 1997-12-06
Filing date: 2000-06-06
Publication date: 2002-02-26

Abstract

The invention relates to a device for fastening a tool (7) on a driveable tool spindle (4) of a machine tool in a progressively adjustable manner. In order to provide such a device which permits an exact adjustment of the tool (7) in the range of micrometers while simultaneously avoiding centrifugal force-related balance errors, the invention provides that the tool (7) is fastened on a tool carrier (6) such that it can be changed out and the tool carrier is mounted in a housing (9) such that it can pivot around a tool carrier rotating axis (8) which preferably forms a right-angle with the tool spindle rotating axis (5).

Description

DEVICE FOR SETTING IN A PROGRESSIVELY ADJUSTABLE WAY A TOOL IN A CONTROL SCREW, A TOOL MACHINE FIELD OF THE INVENTION The invention relates to a device for infinitely varying a support of a tool on a control spindle, of a machine tool. The tool is fixed interchangeably to a tool holder that is installed in a housing, in order to rotate about an axis of rotation of the tool holder that extends at an angle, preferably at a right angle, towards the axis of rotation of the spindle.

BACKGROUND OF THE INVENTION For the infinitely variable adjustment of the tool support in a machine tool, for example a lathe, so-called facing cars are known in practice. These facing carts comprise a carriage that moves translationally by means of which the tool can move towards the work piece. For the equalization of the imbalances related to the centrifugal force that arise during the sliding of the trolley, the known facing trolleys have equalization either through an opposite movement trolley or through counterweights. A disadvantage with those known devices for infinitely variable support of a tool in a spindle of a machine tool, is that on the one hand only translational movement of the tool can occur, and on the other hand, due to residual imbalances and to the centrifugal forces infinitely variable adjustment is possible within a range of one millimeter at high machining speeds.

Another possibility for removing the toolholder with continuous progression is described in patent FR459327. This document teaches a tool holder with characteristics similar to those formulated in the preamble of claim 1. The tool holder is rotated by turning the adjusting screw, whose rope is held at one end with a threaded section of the tool holder inside the housing . 10 The possibility of adjusting has the disadvantage that it is only possible by manually operating the machine and it is necessary to stop its operation completely. It is also difficult to achieve the position required to make adjustments with the adjusting screw. SUMMARY OF THE INVENTION It is an object of the invention to provide a device for the infinitely variable adjustment of a tool on a control spindle of a machine tool which, with almost perfect equalization of the imbalances related to the centrifugal force, allows the complete adjustment of the tool within a range of one millimeter. This object is achieved according to the invention by the fact that the tool is fixed interchangeably to a tool holder that is installed in a housing, in order to rotate about an axis of rotation of the tool.

The tool holder extends at an angle, preferably at a right angle, to the axis of rotation of the spindle by means of a magnetically driven motor or by a hydraulic drive. By rotating the tool holder around an axis that intersects the axis of rotation of the spindle at an angle, preferably a right angle, there is the possibility of equalizing the masses of the tool holder and the tool located on both sides of the axes of rotation in such a way that , the center of gravity of the mass is at the point of intersection of the axis of rotation and the axis of rotation, so that, in the rotation of the tool holder installed in an adjustable manner in the housing, there is no imbalance that arises due to the centrifugal force. Only due to this prevention of imbalances related to the centrifugal force it is possible to adjust the tool holder and therefore the tool, so sensitively, that movement changes are possible within a range of one millimeter, which in turn are a continuous adjustment condition, in particular through CNC. Due to the rotary installation of the tool holder, it is also possible with the device according to the invention to carry out not only the strictly translational movements of the tool. In accordance with the invention, the tool holder is rotated by a motor, magnetically operated or by a hydraulic drive. According to the invention, the tool holder has a lateral surface which is located in the cylinder chamber of the housing and which can accept a fluid on the opposite sides. With a rotary piston construction provided with a hydraulic drive it is possible to rotate the tool holder in a sensitive and simple manner. According to a practical embodiment of the tool holder, - provided with a rotating piston, the tool holder is then constructed in the shape of a disk with a rotating piston integrally formed in the shape of a ring section, which is installed in a chamber of the housing cylinder formed into annular sections. In this mode, the turning piston formed in annular sections constitutes the counterweight for the real tool holder together with the tool, due to which in turn the mass equalization occurs. Furthermore, with the invention it is proposed that the lateral surfaces and the end faces of the tool holder and the rotary piston are constructed as guide surfaces relative to the housing. In this embodiment, the side surfaces and the end faces simultaneously form the sealing surfaces when a hydraulic drive is provided as the drive for the turning piston. In order to allow the adjustment of the tool holder and consequently the tool without play and without transmission error according to a preferred embodiment of the invention, a measuring system is installed between the housing and the tool holder. Direct means in this connection, that the measuring system directly registers the adjustment of the toolholder without the interposition of additional transmission elements. Finally, with the invention it is proposed that the tool be releasably attached to the tool holder in a non-rotating manner by means of a rapid change system with exact repetition. By using such a rapid change system, it results that on the one hand the tool change can occur completely automatically without long interruption times, and on the other hand, by the non-rotating union of the tool with exact repetition, - guarantees that due to the geometries of the known tool, it can continue machining without re-alignment and measurement of the tool. According to a practical embodiment of the invention, the gaseous and / or liquid media for purposes of cooling, cutting and cleaning, can supply the tool with the rapid change system and / or the tool through the tool holder. These gaseous and / or liquid media can be, for example, compressed air for cleaning, lubricating oil for cutting and cooling, or nitrogen for cooling.

BRIEF DESCRIPTION OF THE DRAWINGS The additional features and advantages of the invention are apparent from the description of the following associated drawings, in which the construction of a practical example of a device according to the invention for the infinitely variable support of a tool in a control spindle of a machine tool. The drawings show: Figure 1, a schematic construction of a machine tool with the spindle of the workpiece and the tool spindle, displaced from the parallel axis; Y 2 shows a schematic view from the top of the infinitely variable support of a tool according to the invention.

DETAILED DESCRIPTION OF THE INVENTION In figure 1, the basic construction of a machine tool is shown schematically. The machine tool, not shown in more detail, than with the placement on the plate of at least one workpiece comprising a control spindle 1 of the workpiece, by which the workpiece is rotated around a rotation axis 2 of the workpiece. The machine tool further includes a carriage 3, by means of which a spindle 4 moves both radially to the axis of rotation 2 of the workpiece and axially in the longitudinal direction of the axis of rotation 2 of the workpiece, wherein the spindle 4 is driven in rotation about an axis of rotation 5 of the spindle. As can also be seen from FIG. 1, the spindle 4 comprises a tool holder 6, to which an interchangeable tool 7 is non-rotatably connected. This tool holder 6 is installed in a housing 9, in order to rotate about an axis of rotation 8 of the tool holder operating at an angle towards the axis of rotation 5 of the spindle. Due to the rotary installation of the tool holder 6 in the housing 9 of the spindle 4, with a machine tool constructed in this way, it is possible to move the tool 7 not only transversely by adjusting the spindle 4 by the carriage 3 towards the axis of rotation 2 of the workpiece, but also additionally rotate the tool 7 relative to the axis of rotation 2 of the workpiece. The more detailed construction of the tool holder 6 is shown schematically in FIG. 2. To support the tool 7, the tool holder 6 comprises a rapid change system 10, in which the tools 7 to be used on each occasion can be fixed in a non-rotating manner. and with exact repetition. It is essential to fix the tools 7 with repetition - exact for the constant accuracy of the mechanization, since the geometrical dimensions of each tool 7 go according to the initial values towards the programs of the machine-controlled machining of the machine tool. Therefore, despite the known geometry of the tool 7 used, the non-usable workpieces would be produced by inaccurately placing a tool 7 in the tool holder 6, since the tool 7 would not be placed in the correct position in relation to the tool 7. the rotation axes 2, 5 and 8. In the embodiment shown of a device for the indefinitely variable support of a tool 7 on a control spindle 4 of the machine tool, the tool holder 6 is provided with a rotating piston 11 which , installed in a cylinder chamber 12 of the housing 9, can accept fluid to rotate the tool holder 6. The tool holder 6 then constructed in the shape of a disk with the rotary piston 11 integrally formed conforms to annular sections, is rotated about the axis of rotation 8 of the tool holder, which operates at right angles towards the axis of rotation 5 of the spindle in the mode shown. The tool holder 6 is rotated by the fact that a fluid is introduced through supply means, not shown in greater detail, into the cylinder chamber 12 also formed into annular sections. When the fluid is pumped around a compartment 12a towards the other compartment 12b of the cylinder chamber 12a, a different pressure is applied to the end faces 11a of the rotary piston 11, so that the rotary piston 11 is rotated about the axis of rotation 8 of the tool holder. The lateral surfaces 6a and 11b of the tool holder 6 and the rotary piston 11 and also the end faces 11a of the rotary piston 11 serve in the embodiment shown as guide surfaces relative to the housing 9. At the same time, these surfaces 6a, 11a and 11b serve as sealing surfaces for fluid introduced into the cylinder chamber. In order to achieve the installation of the tool holder 6 in the housing 9 with as little friction as possible, it is possible to provide at least the lateral surfaces 6a and 11b of the tool holder 6 and the turning piston 11 with a coating that reduces the frictional resistance. By installing a direct measurement system 13 between the housing 9 and the tool holder 6, it is possible to measure the degree of rotation of the tool holder 6 without play and without transmission error. The direct metering system 13 can for example consist of a measuring tape which is installed on the lateral surface 11 b of the rotary piston 11 and which is directly tracked by a tracking system installed in the housing 9. When rotating the tool holder 6 around the axis of rotation 8 of the tool holder which intersects the axis of rotation 5 of the spindle at an angle, preferably a right angle, arises the possibility of equalizing the masses of the tool holder and the tool 7 located on both sides of the axis of rotation 8 of the tool holder, in such a way that the center of gravity of the mass lies at the point of intersection of the axis of rotation 8 of the tool holder and of the axis of rotation 5 of the spindle. Therefore, when rotating the tool holder 6 installed in an adjustable manner in the housing 9, there is no unbalance due to the centrifugal force, which would make it impossible to accurately drive the tool 7. Only due to this prevention of the imbalances related to the force centrifugal, it is possible to adjust the tool holder 6 and the tool 7 so sensitively that movement changes within a range of one millimeter are possible. For the additional compensation of the centrifugal forces occurring at the speeds of the axis of rotation 5 of the spindle at well above 15,000 revolutions per minute, the housing 9 can be surrounded by an outer pressure sheath 14 as is the case in the embodiment shown . Naturally, the device described above for an infinitely variable tool support 7 can be used in any kind of machining stations, not only in lathes, as is the case in the embodiment shown.

- - List of reference numbers 1 spindle of workpiece 2 axis of rotation of the workpiece 3 trolley 4 spindle 5 spindle rotation axis 6 toolholder 6a lateral surface 7 tool 8 axis of rotation of the toolholder 9 housing 10 quick change system 11 rotary piston 11a end face 11 b lateral surface 12 cylinder chamber 12a compartment 12b compartment 13 measuring system 14 pressure sleeve

Claims

CLAIMS 1. A device for infinitely varying a support of a tool on a control spindle (4) of a machine tool, wherein the tool (7) is interchangeably joined to a tool holder (6) which is installed in a housing (9) in order to rotate about an axis of rotation (8) of the tool holder extending at an angle, preferably at a right angle, towards the axis of rotation (5) of the spindle, characterized in that the tool holder (6) ) rotates in the housing (9) by means of a motor, driven magnetically or by means of a hydraulic drive.
2. The device according to claim 1, characterized in that the tool holder (6) is provided with a rotating piston (11) which is installed in a cylinder chamber (12) of the housing (9) and can accept a fluid in the opposite sides.
3. The device according to claim 3, characterized in that the tool holder (3) is then constructed in the shape of a disk with the rotary piston 11 integrally formed in annular sections which is installed in sealed relation in a shaped cylinder chamber in annular sections (12) of the housing (9).
4. The device according to claim 4, characterized in that the lateral surfaces (6a, 11b) and the end faces (11a) of the tool holder (6) and the rotary piston (11) are constructed as guide surfaces in relation to the accommodation (9). - -
5. The device according to one or more of claims 1 to 5, characterized in that a direct measurement system (13) is installed between the housing (9) and the tool holder (6).
6. The device according to one or more of claims 1 to 6, characterized in that the tool (7) is releasably joined to the non-rotating tool holder (6) by means of a rapid change system (10) with exact repetition.
7. The device according to claim 7, characterized in that the gaseous and / or liquid medium can be supplied to the rapid change system (10) and / or to the tool (7) through the tool holder (6).