Apparatus for providing a complete tool

An apparatus for provisioning, in particular automatically, a complete tool having a toolholder and a tool, in particular a drilling and/or milling tool. The apparatus has a spindle that can be driven in rotation by a driving device. The spindle has a holding device for holding a toolholder. A measuring device, in particular an optical measuring device, measures a complete tool, held on the spindle. A heating device in the region of the spindle heats a shrink-fit chuck of the toolholder held on the spindle. A cooling device, in particular a cooling device associated with the spindle, enables the spindle and/or the complete tool held on the spindle, to be cooled.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority, under 35 U.S.C. § 119, of German patent application DE 10 2019 124 428, filed Sep. 11, 2019; the prior application is herewith incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention relates to an apparatus for the provision, in particular automated provision, of a complete tool, to a shrinkage and measurement station, to a provisioning system, in particular automated provisioning, of a complete tool having the shrinkage and measurement station, and also to a method for operating the provisioning system.

For machine tools that operate at high speeds or with special precision requirements, especially drilling or milling machines or lathes, the use of shrink-fit chucks is widespread since they operate with a particularly high concentricity and particularly reliable torque transmission between the toolholder and the tool. Such toolholders have a central receiving opening, the diameter of which is slightly smaller than the outside diameter of the tool to be received. To insert the tool into the toolholder, the holder is heated, for instance by using an inductive heating device or a heating blower, until the receiving opening has expanded sufficiently for the tool to be inserted. When the toolholder cools down, where applicable with the assistance of a cooling device, the toolholder shrinks and clamps the tool reliably and on all sides. To remove the tool, the toolholder is once more heated until the tool can be pulled out of the receiving opening.

It is furthermore customary to measure a complete tool consisting of a toolholder and a shrunk-in tool before coupling to a machine tool, e.g. a machine tool designed as a CNC machining center, by means of a measuring device or pre-adjustment device and to use the dimensions determined to optimize the machining of the workpiece. During this process, it is in particular the length of the complete tool, the diameter and the shape of the cutting edge of the clamped tool which are measured. A measuring device of this kind generally has a spindle that can be driven in rotation by means of a driving device and has a holding device for holding a toolholder or a complete tool. Here, the complete tool is rotated axially by means of the spindle during measurement.

United States published patent application US 2006/0021208 A1 and its counterpart German published patent application DE 102 49 072 A1 disclose a method for securing a tool in a tool chuck, in which an actual position of the tool, particularly in the direction of the longitudinal axis of the tool, is first of all determined by measurement. The tool is then inserted into the tool chuck, positioned there on the basis of the actual position determined, and finally shrunk in. After shrinking in, the actual position of the tool in the tool chuck is then determined. During the shrink-fitting process and the determination of the actual positions of the tool, the tool chuck is in this case held on a CNC-controlled tool mounting spindle that can be rotated about an axis of rotation. Moreover, the toolholder and the tool are connected and the complete tool measured in a largely auto-mated way here. In this case, the toolholder and the tool are moved by means of a tool chuck changer and a tool gripper.

In the case of such shrink-fitting and measurement on a spindle, there is a relatively high heat input into the spindle, however, especially in the case of a high number of shrink-fitting and measurement processes within a short time, and this leads to a thermal expansion of the spindle and thus to a reduction in the measurement accuracy. Moreover, the use of a tool chuck changer to move the toolholder and of a separate tool gripper to move the tool is complex.

BRIEF SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide an apparatus for the provision, in particular automated provision, of a complete tool comprising a toolholder and a tool which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which provides for the provisioning of complete tools in a simple and effective manner with a high repeatability. It is a further object of the invention to make available an apparatus for the provision, in particular automated provision, of a complete tool comprising a toolholder and a tool, which has a particularly simple, effective and flexible construction.

With the above and other objects in view there is provided, in accordance with the invention, an apparatus for provisioning a complete tool with a toolholder and a tool, the apparatus comprising:

a spindle to be driven in rotation by a driving device, said spindle having a holding device for holding the toolholder;

a measuring device for measuring the complete tool held on said spindle;

a heating device for heating a shrink-fit chuck of the toolholder held on said spindle; and

a cooling device configured for cooling at least one of said spindle or the complete tool held on said spindle.

In other words, an apparatus for the provision, in particular automated or automatic provisioning, of a complete tool comprising a toolholder and a tool, in particular a milling tool, is proposed, having a spindle that can be driven in rotation by means of a driving device, wherein the spindle has a holding device for holding a toolholder, wherein a measuring device, in particular an optical measuring device, for measuring a complete tool, held on the spindle, and a heating device for heating a shrink-fit chuck of a toolholder held on the spindle are arranged in the region of the spindle. According to the invention, a cooling device, in particular a cooling device associated with the spindle, by means of which the spindle and/or a complete tool held on the spindle can be cooled, in particular air-cooled, is provided.

In this way, it is possible to provide complete tools with high repeatability and accuracy since heating of the spindle is counteracted by cooling the spindle. As a result, the thermal expansion of the spindle is reduced, and the measurement accuracy of the measuring device is effectively increased. In particular, it is also possible here to provide a higher number of complete tools within a defined period of time since it is no longer necessary to allow the spindle to cool down before a subsequent measurement process.

In a preferred embodiment of the apparatus according to the invention, the cooling device is formed by a cooling element which is associated with the spindle and by means of which the spindle can be air-cooled, in particular a ring-shaped and/or disk-shaped cooling element. It is thus possible to achieve effective cooling of the spindle with a simple construction. In particular, it is also possible to retrofit a cooling element of this kind with little effort on a spindle. Here, the cooling element is preferably manufactured from a material that has a high thermal conductivity, e.g. aluminum.

As an alternative to air cooling, the spindle could also be cooled by means of a coolant cooling system, in particular by means of a water cooling system. In this way, it is likewise possible to achieve effective cooling of the spindle. In this case, the cooling liquid could be passed through channels introduced into the spindle or through at least one heat sink resting against the spindle, for example.

One expedient possibility is for the cooling element to surround in a ring shape a spindle element of the spindle and/or an adapter element of the spindle, said adapter element being releasably connected to the spindle element and having the holding device. It is preferred here if the cooling element surrounds in a ring shape a holding section of the spindle, said holding section having the holding device. At this holding section, heat is transferred from a heated complete tool to the spindle, and thus such an arrangement of the cooling element counter-acts heating of the spindle in a particularly effective manner.

For effective cooling of the spindle, the ring-shaped cooling element can rest by means of an inner circumferential wall, in particular in surface contact, against the spindle. Alternatively, or in addition, it is also possible for the cooling element to rest by means of at least one end wall, in particular in surface contact, against the spindle.

In a preferred specific embodiment, the cooling element has an inner region, in particular a ring-shaped and/or sleeve-shaped inner region, and a plurality of cooling ribs, which project outward from the inner region, in order to achieve a simple and effective construction. Provision is preferably made here for the cooling ribs to have a profile which is arc-shaped or, in some section or sections, rectilinear, in a plan view of the cooling element.

One expedient possibility is for the holding device of the spindle to be designed to receive a machine tool interface of a toolholder. More specifically, the holding device of the spindle can have a steep taper (SK) interface, a hollow shank taper (HSK) interface or a polygonal shank taper (PSK) interface, for example.

For effective measurement of a complete tool, the optical measuring device can have at least one image acquisition device, in particular a camera, for acquiring images and/or film recordings of a complete tool held on the spindle. One expedient possibility is for the measuring de-vice to have a signal link to a screen and/or to a data transmission device for the transmission, in particular wireless transmission, as data of complete-tool dimensions determined, in particular to an RFID chip. Here, data transmission can also take place via Bluetooth, QR/data matrix or barcodes, for example.

In one specific embodiment, the heating device can have at least one coil element, which has an induction coil, for heating a shrink-fit chuck of a toolholder, in particular a coil element that can be mounted on a toolholder and/or is ring-shaped. By means of a coil element of this kind, a shrink-fit chuck of a toolholder can be heated effectively and quickly.

In another preferred embodiment, at least one, in particular coolant-cooled, cooling pot for cooling a complete tool can be provided, wherein a complete tool can be arranged partially or completely in an interior space of the cooling pot, in particular in an upside down orientation, and can be brought into contact, in particular surface contact, with a cooled inner wall of the cooling pot, in particular by means of a shrink-fit chuck section of a toolholder of the complete tool. A measured complete tool can be cooled effectively and quickly on a cooling pot of this kind that is separate from the spindle, in particular spaced apart from the spindle.

For simultaneous cooling of a plurality of measured complete tools, a plurality of cooling pots that are spaced apart from one another and/or arranged in series can be provided. One expedient possibility is for the at least one cooling pot to be fixed by means of at least one connecting element, in particular by means of at least one connecting screw.

With the above and other objects in view there is also provided, in accordance with the invention, an apparatus for the provision, in particular automated provision, of a complete tool comprising a toolholder and a tool, in particular a milling tool, having a controllable movement device, in particular having a controllable robot arm, for picking up and moving an object, wherein the movement device has a gripper for picking up a toolholder as an object, in particular at a gripper groove of the tool-holder. According to the invention, a tool, in particular a rod-shaped tool, as an object can also be gripped and/or picked up by means of the gripper.

By means of a gripper of this kind, particularly simple, effective and flexible provision of complete tools is made possible since it is now possible to grip or pick up both toolholders and tools by means of a single gripper. In this way, automated provision or production of a complete tool can be achieved by means of a single gripper, for example.

Here, the movement device is preferably designed in such a way that both positioning of the gripper by translation along three perpendicular axes (x, y, z) and orientation of the gripper by rotation around three perpendicular axes are possible.

In a preferred embodiment, the gripper is of multipart design, wherein a first and a second gripper part of the gripper each have a toolholder gripping contour, in particular an arc-shaped toolholder gripping contour, for picking up a toolholder and a tool gripping contour for picking up a tool, wherein the gripper parts are held on a controllable actuator of the gripper, by means of which a spacing of the gripper parts can be adjusted, wherein at least one object can be clamped by reducing the spacing of the gripper parts. A simple and functionally reliable construction of the gripper is thus achieved.

One expedient possibility here is for the tool holder gripping contour and the tool gripping contour of the respective gripper part to be arranged spaced apart from one another. For a construction which is simple in terms of manufacture, the first and the second gripper part can be formed in mirror symmetry with one another and/or can be formed by identical components, in particular plate-shaped components.

With the above and other objects in view there is also provided, in accordance with the invention, a shrinkage and measurement station having at least one of the apparatuses according to the invention.

Moreover, a system for the provision, in particular automated provision, of a complete tool consisting of a toolholder and a tool, in particular a milling tool, having the shrinkage and measurement station according to the invention is claimed. Here, provision is preferably made for the system to have a balancing station for checking the balance of a complete tool and/or for balancing a complete tool.

With the above and other objects in view there is also provided, in accordance with the invention, a method for operating the system as described.

The advantages obtained from the shrinkage and measurement station according to the invention, the system according to the invention and the methodology according to the invention are identical with the already acknowledged advantages of the apparatuses according to the invention, and therefore they are not repeated at this point.

The advantageous embodiments and/or developments of the invention which have been explained above and/or presented in the dependent claims can be employed individually but also in any desired combination—except in the cases where there are clear dependency relationships or mutually exclusive alternatives, for example.

Although the invention is illustrated and described herein as embodied in apparatus for the provision, in particular automated provision, of a complete tool, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawing in detail and first, in particular, toFIG.1thereof, there is shown a system1according to the invention for the automated provision or production of complete tools3comprising toolholders5and tools7. The system1comprises a mobile tool carriage9, which is loaded with a plurality of toolholders5and a plurality of tools7, which are here designed as milling tools by way of example. The tool carriage9is arranged in the vicinity of a controllable movement device, which is here designed as a robot arm11by way of example, by means of which the toolholders5and the tools7can be moved within the system1. In this case, the tool carriage9is situated in the gripping range of a gripper13of the robot arm11. As an alternative to the tool carriage9, the system1could have a high-bay rack, for example. Feeding could furthermore also be performed by means of a chain magazine or wheeled magazine for toolholders5, for example. Feeding by means of a continuous conveyor belt would likewise be possible.

Here, the robot arm11is designed in such a way that the position of the gripper13can be changed by translation along three perpendicular axes (x, y, z) and the orientation or alignment of the gripper13can be changed by rotation around three perpendicular axes.

The gripper13is shown in an enlarged illustration inFIG.7. By means of the gripper13, both the toolholders5and the tools7can be picked up. According toFIG.7, the gripper13is of multipart design, wherein the gripper13has a first gripper part15and a second gripper part17. Each gripper part15,17has a toolholder gripping contour19, which is formed by a recess and, in this case, by way of example, is arc-shaped, for gripping a toolholder5, and a tool gripping contour21, likewise formed by a recess, for gripping a tool7. The gripper parts15,17are held on a controllable actuator23of the gripper13, which is here operated pneumatically by way of example, by means of which a spacing of the gripper parts15,17can be adjusted. By reducing the spacing of the gripper parts15,17, the toolholders5and the tools7can be clamped between the gripper parts15,17and picked up thereby.

To grip a toolholder5, each gripper part15,17furthermore has an inward-projecting web25in the form of a ring segment, by means of which the respective gripper part15,17can engage in an encircling gripper groove27(FIG.3) in the respective toolholder5.

As is furthermore shown inFIG.7, the gripper13furthermore has a sensor29. By means of the sensor29, it is possible to determine whether there is a complete tool3or a toolholder5in the vicinity of the gripper13. Here—by way of example—the sensor29is formed by an ultra-sonic sensor. Moreover, the gripper13also has sensors31,33. In this case, sensor31is associated with the toolholder gripping contour19of a gripper part, while sensor33is associated with the tool gripping contour21of a gripper part. Here, sensor33can be used to determine whether a tool7is currently clamped or has been picked up on the gripper13. By means of sensor31it is possible to determine whether a toolholder5is currently clamped on the gripper13. Here—by way of example—the sensors31,33are formed by inductive sensors. Moreover, each of the sensors31,33, which are pinshaped in this case, is arranged in a recess in the gripper part15and held in the recess by means of a clamping screw35,37.

According toFIG.7, each gripper part15,17is here formed by two interconnected plate bodies39,41. In this case, the plate bodies39,41of the respective gripper part15,17are connected to one another by means of a plurality of connecting elements42, here—by way of example—connecting screws. In this case, the toolholder gripping contour19and the tool gripping contour21are formed on the plate body39of the respective gripper part15,17. Recesses, here—by way of example—bores, are provided in the plate body41of the respective gripper part15,17to connect the gripper parts15,17to the actuator23. Furthermore, the plate bodies41of the gripper parts15,17are of identical design or configuration here. More-over, the gripper parts15,17are of substantially mirror-symmetrical design with respect to one another.

As is furthermore shown inFIG.1, the system1also has a controllable shrinkage and measuring station43. The shrinkage and measurement station43is likewise arranged in the gripping range of the gripper13of the robot arm11. According toFIG.2, the shrinkage and measurement station43has a spindle45, which can be driven in rotation by means of a driving device. The spindle45has a holding device47(FIG.6) for holding a toolholder5or a complete tool3. Here—by way of example—the holding device47is formed by an HSK inter-face. Moreover, the shrinkage and measurement station43also has a measuring device49, here—by way of example—an optical measuring device, arranged in the region of the spindle45for the purpose of measuring a complete tool3held on the spindle45. By means of the measuring device49, it is possible in this case to determine the length of a complete tool3and the diameter of a tool7of the complete tool3, for example. In this case, the spindle45can be rotated axially with the complete tool3held thereon during the measurement of a complete tool3.

Here, the optical measuring device49has a camera51as an image acquisition device for acquiring images and/or film recordings of a complete tool3held on the spindle45. Moreover, the measuring device49also has a signal link to a screen53for displaying the camera recordings. The measuring device49furthermore has a signal link to a data transmission de-vice (not shown here) for the wireless transmission as data of complete-tool dimensions determined to an RFID chip of a toolholder5.

As is furthermore shown inFIG.2, the shrinkage and measurement station43also has a heating device, arranged in the region of the spindle45, for heating the shrink-fit chuck of a toolholder5held on the spindle45. Here, the heating device has a ring-shaped coil element55, which has an induction coil and can be mounted on a toolholder5, for the inductive heating of a shrink-fit chuck.

The construction of the spindle45is now explained in greater detail with reference toFIGS.4to6. InFIG.6, a complete tool3is held on the spindle45. The spindle45has a spindle element57, indicated by dashed lines inFIG.6, and an adapter element59fixed releasably on the spindle element57. On the adapter element59, the holding device47is designed to hold a toolholder5. The spindle element57is held in an axially rotatable manner in a spindle holder61of the shrinkage and measurement station43. In an alternative embodiment of the spindle, the holding device47could also be provided on the spindle element itself, and therefore the adapter element59is then no longer needed here.

As is furthermore apparent fromFIG.6, the spindle45is assigned a ring-shaped cooling element63, by means of which the spindle45is air-cooled. In this way, the heat input into the spindle45is effectively reduced, thereby making it possible to measure complete tools3held on the spindle45with an increased measurement accuracy. If a heated complete tool3is held on the spindle45, this is also cooled by means of the cooling element63.

Here, the cooling element63surrounds in a ring shape the adapter element59of the spindle45. More specifically, the cooling element63in this case surrounds in a ring shape a holding section65of the adapter element59, said holding section having the holding device47. In this case, the ring-shaped cooling element63rests both by an inner circumferential wall67and by an end wall69in surface contact against the adapter element59of the spindle45. In an alternative embodiment of the spindle, the cooling element63could also surround in a ring shape the spindle element57.

The cooling element63here furthermore has a sleeve-shaped inner region71and a plurality of cooling ribs73projecting outward from the inner region71(FIG.5). In this case, each cooling rib73has an inner region with a single rectilinear cooling rib web, which branches outward into two rectilinear cooling rib webs. As an alternative, it would also be possible, for example, to provide cooling ribs that have a single cooling rib web extending continuously in an arc.

As is furthermore shown inFIG.2, the shrinkage and measurement station43also has a cooling device75for cooling measured complete tools3. Here, the cooling device75has a plurality of cooling pots77arranged in series, wherein one complete tool3can be cooled by means of each cooling pot77. For this purpose, a complete tool3can be arranged partially in an interior space of a cooling pot77in an upside down orientation, i.e. with the clamped tool7first, and brought into surface contact by means of a shrink-fit chuck section79(FIG.6) of the toolholder5with a cooled inner wall81of the cooling pot77. Here, the cooling pots77have a liquid cooling system. To secure the cooling pots77on the shrinkage and measurement station43, each cooling pot77has an outward-projecting annular flange82having continuous apertures, through which connecting elements, here—by way of example—connecting screws, are passed. Here, moreover, each cooling pot77is open on the underside.

As is furthermore shown inFIG.1, the system1also has a controllable balancing station83, by means of which the balance of a measured and cooled complete tool3can be checked. Optionally, the balancing station83could also be designed in such a way that a complete tool3can be balanced by means of said station. Moreover, the system1has a mobile tool carriage85, which can be loaded with checked complete tools3. As an alternative to the tool carriage85, the system1could also have a high-bay storage system. The balancing station83and the tool carriage85are likewise arranged in the gripping range of the gripper13of the robot arm11. The system1furthermore also has a control station87, by means of which the robot arm11, the shrinkage and measurement station43and the balancing station83are controlled, thus enabling the system1to be operated in an automated manner. In this case, all the controllable devices of the system1are networked in modular fashion via a master computer of the control station87in terms of data and/or signal transmission.

Illustrative automated operation of the system1and a method for operating the system1will now be explained in greater detail below:

In the initial situation, the tool carriage9is loaded with toolholders5and tools7. First of all, a toolholder5is picked up from the tool carriage9by means of the robot arm11. By means of a cleaning device, e.g. a brush, associated with the tool carriage9for example, a receiving hole of the toolholder5picked up is cleaned. In a similar way, the interface region of the spindle can also be cleaned at regular intervals by means of a wiping device, e.g. a wiping device that can be gripped by means of the robot arm11. The toolholder5is then inserted into the HSK interface of the spindle45by means of the robot arm11. The HSK interface of the spindle45is then closed, with the result that the toolholder5is held firmly on the spindle45. Finally, the toolholder5is identified by an RFID chip attached to the toolholder5, and the relevant program for shrink-fitting a tool7is called.

A tool7is then picked up from the tool carriage9by means of the robot arm11. The tool7picked up has a readable code, e.g. a QR code, barcode or data matrix code, which is read with a reading device mounted, for example, on the robot arm11. After the code has been identified and checked, the toolholder5is heated by means of the heating device53, and the tool5is inserted into the toolholder7by means of the robot arm11. Finally, the tool5is then shrunk into the toolholder7and, in the process, a desired Z dimension or length dimension of the complete tool3is set by means of the robot arm11and the measuring device49. As an alternative to setting by means of the robot arm11, it would also be possible, for example, for the Z dimension of the complete tool3to be set by means of a stop element or stop mandrel, which is mounted on the spindle45and can be extended from the spindle45, as a stop for a tool7inserted into a toolholder5.

The complete tool3is then removed from the spindle45and inserted for cooling into one of the cooling pots77by means of the robot arm11until the complete tool3reaches the desired temperature, e.g. room temperature. In this case, the temperature of the complete tool3is measured by means of a temperature sensor of the respective cooling pot77. The cooled complete tool3is then removed from the cooling pot77by means of the robot arm11and inserted into the balancing station83to check the balance. The spindle of the balancing station83can also be cleaned at regular intervals by means of a wiping device, e.g. one that can be gripped by the robot arm11. After this check, the complete tool3is removed from the balancing station83by means of the robot arm11. Before the measurement of the cutting edges of the complete tool3, the cutting edges are cleaned of dust and other adhesions, e.g. by dipping the cutting edge region of a complete tool3into a cleaning bath or by dabbing with an adhesive compound. The complete tool3is then inserted into the HSK interface of the spindle45. The HSK interface of the spindle45is then closed, with the result that the tool-holder5is held firmly on the spindle45. Finally, the complete tool3is re-identified by the RFID chip attached to the toolholder5, and the relevant program for measuring the complete tool3is then called. The complete tool3is then measured by means of the measuring device49. During this process, the complete tool3is rotated axially by means of the spindle45. After measurement, the complete tool3is removed from the spindle45and placed on the tool carriage85by means of the robot arm11. If the balance of the complete tool3is inadequate, it can be additionally balanced manually by a worker.

In an alternative mode of operation, the system1may also be used to shrink tools7out of toolholders5.