DE102006005760B4 - Machine tool spindle - Google Patents

Abstract

Machine tool spindle with a fluid integrated into the machine tool spindle Fluid unit for generating a hydraulic and / or pneumatic Force, characterized in that the fluid unit at least a storage device for storing the fluid and a pressure generating unit For pressurizing the fluid.

Description

The The invention relates to a machine tool spindle according to the preamble of claim 1.

In Machine tools, especially in milling machines, are very often tool clamps used, which allow automatic tool change. This means that the tool is so with the shaft of the machine tool spindle connected, that it can be solved automatically. For clamping one uses in the predominant one Number of cases Tool clamps, which are connected to a spring assembly. The resulting spring force is transmitted via the pull rod on collet segments, which in turn connect the tool to the shaft.

To the Will solve the drawbar and thus also the plate-spring package with an axially acting force acted upon, which compresses the springs together and thus an axial displacement allows the drawbar which in turn leads to a release movement the clamping segments in the tool holder leads.

The to release necessary axial force is over so-called dissolving units generated. This is usually a piston-cylinder system, which is pressurized on one side with pressure. This pressure multiplies with the area of Piston acts as a solvent over a Pressure contact on the drawbar.

Of the to release the pressure required by the tool is either generated hydraulically, being here usually on the machine tool anyway existing hydraulic unit back or when using pneumatic release units will be in many workshops any existing air pressure used anyway.

It is easy to see that due to the smaller size of the air pressure (usually 5-6 bar) in pneumatic release units a significantly larger area or a power translation becomes necessary. Hydraulic release units usually work in the range of about 80-100 bar, depending on the existing Hydraulic unit.

It is characteristic for both systems that the pressure outside the spindle or spindle complex is generated in separate pressure generators (either hydraulic unit or air compressor). Such systems show z. B. the publications DE 19859 669 A1 or DE 100 07 126 A1 ,

task The invention is therefore, a machine tool spindle with a a fluid-comprising fluid unit for generating a hydraulic and / or pneumatic force, to propose that economically better can be produced and / or particularly compact formable.

These Task is, starting from a machine tool spindle of the introductory described type, by the characterizing features of the claim 1 solved.

By in the subclaims mentioned measures are advantageous embodiments and further developments of the invention possible.

Accordingly a machine tool spindle according to the invention is characterized characterized in that the fluid unit at least one storage device for storing the fluid and a pressure generating unit for pressurizing of the fluid.

With Help such in the motor spindle, in particular for a machine tool, integrated fluid unit is a largely self-sufficient pressure generation possible. This can be both economical and very compact will be realized.

advantageously, For example, very small units are used consist of high-pressure pump, valve block and oil reservoir. in this connection can be due to an electrical control in the motor spindle preferably integrated fluid unit directly at the place of the necessary Movement a hydraulic or possibly a pneumatic Create pressure.

Preferably is the one to solve a tool necessary hydraulic pressure and flow through designed as a compact hydraulic unit Fluid unit generated. These units are in an advantageous manner characterized in that they have a relatively high pressure, z. B. about 200 bar, in particular combined with a relatively small Provide volume flow can.

One embodiment could be, the compact hydraulics directly in the back of the spindle to install, d. H. the compact hydraulics directly to the spindle too fix z. B., so consuming piping and / or the enlargement of the to release necessary volume flow can be omitted.

Especially advantageous is the use of compact hydraulic units then, on the one hand no additional machine hydraulics is provided, so usually the function of the release unit can only be generated by a very expensive pneumatic cylinder could.

In a particular embodiment of the invention can be a compact hydraulic unit used, essentially from commercial Components exists, the z. B. already be used in large quantities.

advantageously, a unit designed as a fluid unit is used, the preferably already commercially available is.

These Combination allows on the one hand, the substitution of the relatively expensive pneumatic release unit and guaranteed on the other hand, a relatively low initial price the compact hydraulics.

The Depending on the application, power is supplied in 12, 24, 48 or 220 V, the control is controlled by the usual or voltage signals ensured.

One embodiment The invention is illustrated in the drawing and is based on the Figure closer below explained.

in the Individual shows:

1 a schematic sectional view through a motor spindle according to the prior art with pneumatic release unit,

2 a schematic sectional view through a motor spindle with a release unit according to the invention and

3 a schematic sectional view of an enlarged section of a motor spindle with a release unit according to 2 ,

In 1 is schematically a motor spindle 1 with a release unit 20 according to the prior art for releasing a tool not shown in a clamping device 3 with drawbar 4 shown.

In 2 and 3 is a compact hydraulics 2 in conjunction with a release unit 3 , as well as a rotary feedthrough 5 represented according to the invention. The compact hydraulics 2 includes an electric motor, a pump, a reservoir for the fluid, in particular hydraulic oil, a valve block, and an electrical control unit, which is not shown in detail for reasons of clarity.

The in the compact hydraulic 2 Volume flow generated with high pressure acts on the piston cylinder system of the release unit 3 which converts the pressure across the piston surface into the axial force necessary to release the tool. The inventive structure still allows the use of a standard rotary feedthrough 5 as it is necessary for many applications in the machine tool industry. By the described construction, a particularly compact and economically favorable solution for releasing the tool can be realized.

In addition, only electrical cables or the like are necessary to the operation of the release unit 2 to ensure according to the invention. A supply of pneumatic and / or hydraulic conduits or the like, as is essential according to the prior art, is not required according to the invention. This will both the assembly and disassembly, maintenance, etc. of the motor spindle 1 as well as the operational safety of the motor spindle 1 decisively improved.

Generally, the electrical energy / signal transmission 18 not only touching by slip ring carrier or the like, but also non-contact such. B. be realized by means of radio transmission or by means of inductive energy transfer.

For example For example, one and / or more rotating components may be an electrical Energy storage such as a battery and / or rechargeable battery include, so that z. B. the assembly / s and / or a transmitter / receiver for the control signals can be supplied with energy is. Preferably, this energy storage is exchanged at intervals or charged. With this measure may possibly waive electrical sliding contacts completely or partially become.

Claims (12)

Machine tool spindle having a fluid unit comprising a fluid integrated in the machine tool spindle for generating a hydraulic and / or pneumatic force, characterized in that the fluid unit has at least one storage device for storing the fluid and a pressure generating unit for pressurizing the fluid. Machine tool spindle according to claim 1, characterized characterized in that a holding device for holding a tool or workpiece is provided. Machine tool spindle according to claim 2, characterized characterized in that a release unit to release of the tool or workpiece is provided by the holding device. Machine tool spindle according to claim 3, characterized in that the release unit we at least the fluid unit for hydraulic and / or pneumatic release of the tool or workpiece from the holding device comprises. Machine tool spindle according to claim 2 or 3, characterized in that at least one tension element between the holding device and the fluid unit is arranged. Machine tool spindle according to one of the aforementioned Claims, characterized in that the fluid unit comprises at least one control unit for Check the release unit and / or the holding device. Machine tool spindle according to claim 6, characterized characterized in that at least one control of the control unit is designed as a valve and / or piston. Machine tool spindle according to one of the aforementioned Claims, characterized in that the fluid as a cooling lubricant for the tool is trained. Machine tool spindle according to claim 6 or 7, characterized in that the fluid unit with at least the Storage device and the pressure generating unit and the control unit is designed as a first unit. Machine tool spindle according to claim 6, 7 or 9, characterized in that the machine tool spindle with the at least the storage device and the pressure generating unit and the control unit comprising fluid unit as a second unit is trained. Machine tool spindle according to one of the aforementioned Claims, characterized in that the machine tool spindle as a motor spindle is trained. Machine tool with a machine tool spindle according to one of the preceding claims.