DE102018104199B4 - Machine tool with work area, setup station and robot arm and method for their operation - Google Patents

Abstract

Machine tool (10) with several machine axes (19), with a work space (13) which is set up for machining a workpiece (14), in which a clamping device (15) for clamping the workpiece (14) during machining and a tool spindle ( 16) are arranged to hold a machining tool (17), the tool spindle (16) and the clamping device (15) being movable relative to one another by means of one or more of the machine axes (19), with a control device (18) which is designed to do this to control the workflow of workpiece processing in the work area (13) during a main time, with a setup station (25) which is separated from the work area (13) by a partition (26), with a workpiece holder (28) for holding at the setup station (25). of the workpiece (14) is arranged, with a workpiece changing device (33) which is arranged between the setup station (25) and the work space (13) and is designed to move a workpiece (14) between the setup station (25) and the work space (13 ) to change, with a robot arm (40) which is assigned to the setup station (25) and can be moved in several degrees of freedom, which has a tool holder (43) at its free end (42), and which is set up to be at the setup station (25th) during the main time ) to process the workpiece (14) held in the workpiece holder (28), at least some of the functions implemented in the control device (18) also being used for controlling and / or monitoring the workflow at the setup station (25).

Description

The invention relates to a machine tool with several machine axes and a method for operating it. The machine tool has a work area that is set up to process a workpiece. A clamping device for clamping the workpiece during machining and a tool spindle for receiving a machining tool are arranged in the work space. The tool spindle and the clamping device can be moved and positioned relative to one another by means of one and in particular several machine axes. The workpiece can preferably be processed on several sides.

Such machine tools are known in different designs. There are machining centers that can carry out automatic changes of the machining tool and the workpiece in order to be able to carry out highly precise and complex workpiece machining in one clamping of the workpiece in the work area.

CN 107553198 A describes a production system with automatic loading and unloading using an industrial robot.

A machine tool for machining a workpiece is in DE 10 2009 027 463 A1 described. The workpiece can be re-clamped programmatically, for example using a tool changing system with a double gripper.

It is also known to subject the workpieces to further processing operations before and/or after processing in the working area of the machine tool. For this purpose, separate processing cells can be arranged next to the machine tool and connected to the machine tool using a suitable transfer device. Depending on the machining task, simpler machining steps that, for example, require less precise machining, can be outsourced to simpler machining or robot cells, so that the machining of the workpiece by the machine tool is kept free for those machining steps that are necessary due to their requirements, in particular on the accuracy or the material removal volume that requires processing in the machine tool. Some manufacturers offer such additional processing or robot cells, such as Cellro B.V.

The effort required for such additional processing cells is relatively high. The cells must be connected separately to the energy and media supplies necessary for processing, e.g. compressed air, hydraulics, cooling water and electrical energy. In addition, such additional processing or robot cells with a corresponding part transfer for transporting the workpieces in many cases hinder accessibility to a machine tool, since such additional processing cells are usually placed directly in front of the machine tool. The necessary safety devices with regard to occupational safety must also be provided for the additional processing cell, such as protective cladding and securing the energy and media supply. In addition, the installation area for the machine tool and the additional processing cell is usually large and therefore incurs additional costs when building a factory.

Based on this, it can be seen as the object of the present invention to improve the efficiency of a machine tool with little effort.

This task is solved by a machine tool with the features of patent claim 1 and a method with the features of patent claim 15.

The machine tool has a work area that is set up to process a workpiece. A clamping device for clamping the workpiece during machining and a tool spindle for holding a machining tool are arranged in the work area. The tool spindle can also be set up to automatically change the machining tool. The machine tool has several machine axes. The clamping device and the tool spindle can be moved and positioned relative to one another using one or more of the existing machine axes. The machining tool and the clamped workpiece can therefore also be moved relative to one another in order to carry out the desired machining of the workpiece. The workpiece can preferably be processed by the machine tool from several sides, for example from three, four or five sides. Several tool spindles can also be arranged in the work space, so that the workpiece can be machined simultaneously or one after the other using machining tools of the different tool spindles.

The machine tool also has a setup area that is separated from the work area by a partition. The partition or at least a section of the partition can be opened to transfer a workpiece between the setup station and the work area and then closed again. The partition is, so to speak a common wall of the set-up area and the work area and delimits the set-up area on one side (towards the work area) and the work area on the opposite side (towards the set-up area).

The setup station is intended and set up in particular to prepare the workpiece for processing in the work area. A workpiece holder for holding the workpiece is arranged at the setup station. A workpiece changing device is present, which is arranged between the setup station and the work area and is set up to be able to change or transport a workpiece between the setup station and the work area. Preferably, the workpiece changing device can be set up to take over a workpiece to be processed in the workspace from the workpiece holder of the setup station and to transfer it to the clamping device in the workspace. The workpiece changing device can also be set up to take over a workpiece processed in the workspace from the clamping device in the workspace and to transport it out of the workspace, for example back to the setup station.

A robot arm is assigned to the setup station. The robot arm can be moved in several degrees of freedom and has corresponding translational and/or rotational axes for this purpose, which connect individual links of the robot arm with one another.

The machine tool also has a control device. The control device is set up to control the workflow of workpiece processing in the work area during a main time. The main time is the period of time during which a workpiece is machined in the work area using the at least one tool spindle. The robot arm is set up to process a workpiece held in the workpiece holder at the setup station during this main time. Preferably, at least temporarily during each main time, a workpiece is present at the setup station and held in the workpiece holder, which can be processed using the robot arm.

The machine tool already has all the connections for the required supply of electrical energy and any media, so that the supply of the machine tool's set-up area can be achieved very easily and without much effort. For example, a cooling unit can also be used to cool equipment and/or the workpiece for both the work area and the setup area. In addition, the footprint of the machine tool does not increase or only increases slightly due to the additional robot arm. This means that existing machine tools can also be retrofitted. The small footprint also enables cost savings compared to additional separate processing cells when realizing a production.

At least some of the implemented functions of the control device of the machine tool are also used to control and/or monitor the workflow at the setup station. The control device can therefore have higher-level functions - in particular safety functions that concern occupational safety - which are also used for the operation of the robot arm and do not have to be implemented separately.

Preferably, the control device provides at least one safety function for the operation of the machine tool and in particular the workpiece processing in the work area in order to protect operators from injuries and avoid damage to the material. For example, as a possible safety function, the control device can query at least one sensor signal that indicates whether a door, an inspection flap or another opening in an outer machine wall surrounding the machine tool is open or closed. Machining of the workpiece or movement of a machine axis is only possible if these openings are closed. Such openings can be locked by the control device during machining of the workpiece or movement of a machine axis in order to prevent opening.

Another example of a safety function is ensuring that the movable devices and parts are free of collision, in particular a loading or workpiece transfer unit and the devices that can be moved by machine axes, such as the clamping device, the at least one tool spindle and the workpiece changing device. For this purpose, the control device can query one or more position values and/or sensor signals from monitoring sensors (e.g. proximity sensors, limit switches, etc.).

The control device can therefore use one or more such safety functions or other higher-level controls and/or regulations both for the workflow in the work area and at the setup station, in particular to ensure occupational safety.

The control device can also set position setpoints and/or movement paths for the positioning or alignment or movement of the robot arm or individual limbs of the robot provide rarms. The movement can be carried out by a subordinate and separate robot control that controls the individual rotary or translational robot axis drives. Alternatively, the complete movement control of the robot can be carried out by the control device of the machine tool. The robot arm can be viewed as one or more additional machine axes that are controlled by the common control device.

In addition to processing the workpiece, the robot arm can also be set up or operated to clean the setup area and in particular the workpiece holder.

• - Material abtragende und/oder umformende Bearbeitungen, wie Entgraten, Bohren, Gewindeschneiden, Prägen, usw.
• - das Markieren des Werkstücks, beispielsweise mittels eines Lasers,

• - das Reinigen des Werkstücks mit Druckluft oder einem Reinigungsfluid bzw. einer Flüssigkeit, oder durch Absaugen, beispielsweise von Spänen oder Pulver vom Laserauftragsschweißen
• - das Messen oder Prüfen von Dimensionen am Werkstück,.
• - das Montieren von wenigstens einem Zusatzteil am Werkstück und/oder das Zusammenbauen mehrerer Werkstückkomponenten,
• - das Auftragen von insbesondere metallischem Material oder nichtmetallischem Material wie etwa Kunststoffmaterial auf das Werkstück durch ein additives Herstellungsverfahren (generatives Fertigungsverfahren) wie z.B. Lasersintern, Laserschmelzen, Lichtbogen-Auftragsschweißen bzw. Laserschweißen, Elektronenstrahlschmelzen, Metall-Pulver-Auftragsverfahren oder ein anderes geeignetes Pulverbettverfahren, Freiraumverfahren oder Flüssigmaterialverfahren.
• - Konservierung von Werkstücken durch Auftrag von Konservierungsstoffen

The processing of the workpiece by the robot arm includes, but is not limited to, processing steps that remove material. The processing can include one or more of the following activities or processing steps:

• - Processes that remove and/or shape material, such as deburring, drilling, thread cutting, embossing, etc.
• - marking the workpiece, for example using a laser,

• - Cleaning the workpiece with compressed air or a cleaning fluid or liquid, or by suction, for example of chips or powder from laser deposition welding
• - measuring or checking dimensions on the workpiece.
• - assembling at least one additional part on the workpiece and/or assembling several workpiece components,
• - the application of in particular metallic material or non-metallic material such as plastic material to the workpiece by an additive manufacturing process (generative manufacturing process) such as laser sintering, laser melting, arc deposition welding or laser welding, electron beam melting, metal powder deposition process or another suitable powder bed process, Free space process or liquid material process.
• - Preservation of workpieces by applying preservatives

The robot arm can carry out one or more of these processing steps in any combination and order during main time. It is possible to process the same workpiece several times both at the setup station and in the work area. For example, material applied by an additive manufacturing process can then be processed to create very precise surfaces or edges in the workspace and then conveyed back to the setup station in order to carry out further processing there, for example to apply material additively again.

For additive manufacturing, the robot arm can use a laser welding head as a processing tool. The laser welding head and any additional units for the additive manufacturing process, for example a laser source and a material supply, are arranged at the setup station, preferably as close as possible to the workpiece holder, in order to be able to keep the supply lines between the additional units and the laser head as short as possible. At the setup station, the parts of the machine tool that can come into contact with material during additive manufacturing can be made of stainless steel or other suitable materials or provided with other suitable surface coatings. If necessary, transparent elements in a wall surrounding the setup area must be designed to be suitable for the use of the laser (e.g. use of a laser protection screen). A cooling unit may be required to cool the laser. This cooling unit can cool both the laser at the setup station and machine equipment in the work area. To remove welding powder or slag or to dispose of excess material during additive manufacturing - if technically possible or sensible - the same disposal facility can be used as for chip and coolant removal in the work area.

Through additive manufacturing at the setup station, the production of workpiece variants that are based on the same base body can be simplified. For example, the same cast body can be used as the base body for several or all variants of the workpiece. Depending on the variant to be carried out, the robot arm at the setup station can be used to apply material to the appropriate locations in order to create the different workpiece variants. It is understood that in addition to the material application, other processing can also be carried out - at the setup station and/or in the work area - in order to produce the desired workpiece variant from the base body.

Additive manufacturing processes at the setup station can also be used to create special workpiece surface properties, such as for example to create functional protective layers and/or sliding layers and/or supporting layers on workpiece surfaces.

It is preferred if the workpiece holder is rotatable about an axis of rotation, which is preferably vertically aligned. This allows, for example, a circular material application to be achieved on the clamped workpiece during additive manufacturing. The relative movement between the welding head and the workpiece can be carried out by the rotatable workpiece holder.

In one embodiment of the machine tool, the robot arm is set up to hold a measuring tool or has a measuring tool at its free end. The control device can be set up to control the robot arm with the measuring tool in order to determine the position and/or orientation of the workpiece arranged in the workpiece holder at the setup station in a coordinate system of the robot arm. This measurement can be carried out in order to then be able to carry out further processing of the workpiece at the setup station with the required accuracy. The measurement can also be set up to recognize different types of workpieces.

It is advantageous if the workpiece changing device is set up to simultaneously transport a workpiece to be processed from the set-up area into the work area and an already processed workpiece from the work area to the set-up area. For example, the workpiece changing device can have two workpiece changing stations for one workpiece each and can be pivotally mounted about a pivot axis running between the work area and the setup station. It is also possible that at least part of the partition between the setup station and the work space is connected to the workpiece changing device and is arranged, for example, in a radial plane of the pivot axis of the pivotable workpiece changing device.

In a preferred embodiment, the workpieces are each attached or clamped to a pallet. When processing the workpieces at the setup station and in the work area, the workpiece remains arranged in the same position on the assigned pallet. The pallet is set up for transporting and/or holding or clamping the workpieces.

The workpiece changing device can be designed as a so-called pallet changer. The workpiece changing device can have at least one and preferably two pallet grippers. The pallet grippers are designed to attack the pallet to transport the workpieces.

The workpiece holder at the setup station and the clamping device are designed differently in one exemplary embodiment. In particular, the clamping device can be movable in at least one degree of freedom in which the workpiece holder is immovable and/or the workpiece holder can be movable in at least one degree of freedom in which the clamping device is immovable. The storage and positioning accuracy of the workpiece using the clamping device can be greater than using the workpiece holder. As a result, the mobility and/or design of the workpiece holder can be limited to the accuracy required for processing by the robot arm, which reduces the costs for the workpiece holder compared to the highly precise storage and positioning of the workpiece by means of the clamping device in the workspace. However, it is also possible to carry out the storage and positioning accuracy of the workpiece very precisely using the workpiece holder. Processing can then be carried out with high precision at the setup station using particularly precise robots.

It is preferred if the robot arm is arranged on a base on a base adjacent to the machine bed of the machine tool. This allows the robot arm to be decoupled from the machine bed. If the robot arm is processing the workpiece at the setup station during main time, vibrations can occur due to accelerations during the movement of the robot arm. The vibrations are introduced into the subsurface via the base and not directly into the machine bed. This can ensure that the accuracy of the workpiece machining in the workspace by the at least one machine spindle is not impaired by vibrations introduced due to the robot movement.

It is advantageous if the number of degrees of freedom of the robot arm for the movement of its free end is higher than the number of degrees of freedom in the work space with which the tool spindle, and thus the machining tool, can be moved and positioned relative to the workpiece. This makes it possible to carry out workpiece processing at the setup station, which cannot be carried out due to the less movable tool spindle in the work area. For example, the workpiece can be machined on one or more sides that are not accessible by the tool spindle.

In one embodiment, the tool holder of the robot arm can have a standard interface for interchangeable tools. For example, the standard interface be set up to hold tools with a hollow shank taper (HSK).

A tool magazine with several tools for the robot arm is preferably arranged at the setup station. The tools can be stored independently in the tool magazine or picked up from the tool magazine by the robot arm. The tool magazine is preferably arranged immovably relative to the machine bed or the base of the robot arm. The tool magazine can be omitted if the robot arm only carries out a specific activity and no tool change is necessary.

It goes without saying that more than one robot arm can be assigned to a setup station. It is also possible to assign the same tool magazine to several robot arms. Alternatively, there can be a separate tool magazine for each robot arm.

It is preferred if the machine tool has an outer machine wall that surrounds both the work area and the setup area. The outer machine wall therefore also surrounds the robot arm, so that occupational safety is also guaranteed at the setup station. A separate enclosure for a processing cell that is located upstream or downstream of the machine tool can be omitted.

It is also advantageous if there is a workpiece transport opening in the outer wall of the machine for transporting workpieces to and/or from the setup station. Advantageously, the workpiece transport opening can be the only opening that is set up for conveying workpieces into and out of the machine tool. Within the machine tool, the workpiece transfer takes place between the setup station and the work area through the workpiece changing device. There is no need to feed or remove workpieces directly from the outside into the work area or from the work area to the outside.

It is also advantageous if the machine tool has a removal device for chips and/or coolant. This removal device is designed in such a way that chips and/or coolant can be drained from the machine tool both from the work area and from the set-up area, in particular via a common shaft or channel. This results in a very simple design and reduces costs compared to separate processing cells.

The machine tool can be operated as follows:

First, a workpiece to be processed is transported, for example, from the setup station via the workpiece changing device or by another loading device (e.g. a portal conveyor) directly into the work area. Another workpiece is transported to the setup station; for example, an already processed workpiece can be transported from the work area back to the setup station using the workpiece changing device. Preferably, a simultaneous workpiece change can take place between the setup station and the work area. The workpiece arranged and clamped in the work area is then processed during a main time using the at least one tool spindle. During this main time, the workpiece at the setup station is processed using the robot arm. This other workpiece can be the workpiece previously machined in the workspace. It is also possible to transport the workpiece machined in the work area out of the machine tool without further post-processing and to feed a workpiece that is still to be machined to the setup station and to machine this workpiece that is still to be machined during the main time at the setup station.

Advantageous configurations of the machine tool and the method result from the dependent claims, the description and the drawings. Preferred exemplary embodiments of the invention are explained in detail below with reference to the accompanying drawings. Show it:

1 in plan view a schematic, block diagram-like representation of an exemplary embodiment of a machine tool with a work area, a setup station and a robot arm assigned to the setup station and

2 and 3 the machine tool 1 in a side view similar to a block diagram, with different temporal phases being illustrated.

In the 1 until 3 an exemplary embodiment of a machine tool 10 is illustrated in a highly schematized manner in the manner of a block diagram. The machine tool 10 has a machine bed 11, which is intended and set up for installation on a surface 12, for example in a factory hall. Above the machine bed 11 there is a work space 13 for processing workpieces 14. A clamping device 15 is present in the work space 13 for clamping the workpiece 14 during its processing. In the working space 13 there is also at least one tool spindle 16, which is used to hold a machining tool 17 for machining the Workpiece 14 is set up in the workspace 13. Optionally, a workspace tool magazine 20 and, depending on the mobility of the tool spindle 16, different machining tools 17 can be exchanged in and out of the tool spindle 16 using an optional tool changer, depending on the required machining of the workpiece 14.

The machine tool 10 also has several machine axes 19 that can be controlled by a control device 18. The machine axes 19 of the machine tool are each designed as translational or rotary machine axes 19. The number of machine axes 19 can vary depending on the design of the machine tool 10. Some of the machine axes 19 are arranged in the work space 13 and set up to move and/or align the clamping device 15 and the at least one tool spindle 16 in the work space 13 relative to one another. In particular, the axis arrangement with the at least one machine axis 19 is set up both for moving the clamping device 15 relative to the machine bed 11 and for moving the tool spindle 16 relative to the machine bed 11. The exact axis arrangement depends on the design of the machine tool 10.

In the exemplary embodiment, the machine tool 10 also has a setup station 25. The setup station 25 is separated from the work area 13 by a partition 26. The setup station 25 and the work space 13 of the machine tool 10 are enclosed by an outer machine wall 27 that runs all around.

A workpiece holder 28 for holding a workpiece 14 at the setup station 25 is arranged at the setup station 25.

In the exemplary embodiment, the workpieces 14 are each fastened on a pallet 29 and are transported together with the pallet 29 or using the pallet 29 and held in the workpiece holder 28 at the setup station 25 and clamped in the clamping device 15 in the work space 13. At the setup station 25, a workpiece 14 is made available for processing in the work area 13.

The machine tool 10 has a workpiece changing device 33, which is arranged between the setup station 25 and the work space 13 and, in the exemplary embodiment, partially protrudes into the work space 13 and partially into the setup station 25. The workpiece changing device 33 is arranged in the area of the partition 26 in the preferred exemplary embodiment. By means of the workpiece changing device 33, a workpiece 14 can be transported from the setup station 25 into the workspace 13 and/or from the workspace 13 to the setup station 25. The workpiece changing device 33 is, for example, designed in such a way that a workpiece 14 present at the setup station 25 can be taken over by the workpiece holder 28 and transported into the workspace 13 and/or that a machined workpiece 14 can be taken over by the clamping device 15 and from the workspace 13 back to the setup station 25 can be transported.

In the illustrated embodiment, the workpiece changing device 33 has two pallet grippers 34, with one pallet gripper 34 being arranged at the setup station 25 and the other pallet gripper 34 in the work area 13 immediately adjacent to the partition wall 26 in the starting position. The pallet grippers 34 are set up to pick up a pallet 29 with the workpiece 14 arranged thereon. The workpiece changing device 33 is, for example, pivotable about a pivot axis S, which is arranged parallel to or in the plane of the partition 26. The pallet grippers 34 are arranged on opposite sides with respect to the plane in which the pivot axis S extends. By means of a pivoting movement about the pivot axis S, the pallet grippers 34 can swap places, so that the pallet gripper 34 previously arranged at the setup station 25 is then arranged in the work space 13 and vice versa. If one or both pallet grippers 34 take over a pallet 29 with a workpiece 14 ( 3 ), in this way a workpiece transfer can take place between the setup station 25 and the work area 13. At the same time, a workpiece to be machined can be transported from the setup station 25 into the workspace 13 and an already machined workpiece can be transported from the workspace 13 back to the setup station 25. The workpiece holder 28 or the clamping device 15 can be moved via one or more machine axes 19 at the setup station 25 and one or more machine axes 19 in the work area 13 in such a way that the pallet 29 with the workpiece 14 is arranged on the associated pallet gripper 34 or removed from the associated pallet gripper 34 can be. According to the example, the workpiece changing device 33 is only rotatable about the pivot axis S and is otherwise not designed to be movable in a rotational or translational manner. It is understood that the pallet grippers 34 can have clamping means for holding the respective pallet 29 in a non-positive and/or positive manner.

The workpiece holder 28 can be rotated about an axis of rotation D by means of at least one machine axis 19. This makes it possible to drive a workpiece 14 arranged in the workpiece holder 28 so that it rotates about the axis of rotation D and thereby as will be explained in more detail below. The axis of rotation can, for example, be aligned vertically.

A partition section 26a of the partition 26 is connected to the workpiece changing device 33, for example. When the workpiece changing device 33 rotates about the pivot axis S, the partition section 26a also rotates. This creates a kind of revolving door in the partition 26, so that a pallet 29 with a workpiece 14 can be conveyed between the setup station 25 and the work space 13.

In addition to the machine axes 19, the control device 18 also controls the movement of the workpiece changing device 33.

For example, a workpiece transport opening 35 is present in the machine outer wall 27. Through the workpiece transport opening 35, a pallet 29 with a workpiece 14 can be fed to the setup station 25 and a workpiece 14 arranged at the setup station 25 can be conveyed out of the machine tool 10, which is shown schematically in 2 is illustrated by the double arrow. Apart from the partition wall section 26a, the working space 13 can therefore be designed without any further openings for the workpiece transfer.

The workpiece transport opening 35 can preferably be closed via a door, flap or the like. The workpiece transport opening 35 is closed during processing. In the exemplary embodiment illustrated here, the workpiece transport opening 35 can be arranged such that a linear transport of the workpieces 14 through the workpiece transport opening 35 to the workpiece holder 28 and from the workpiece holder 28 to the workpiece changing device 33 is possible.

Alternatively, workpieces 14 can also be conveyed via a portal conveyor from above to the setup station 25 or away from the setup station 25. In this variant, often only the workpieces 14 are conveyed without a pallet 29. The workpiece 14 is then placed on or removed from the pallet 29 by the portal conveyor.

At the setup station 25, a robot arm 40 is arranged within the machine outer wall 27. The robot arm is arranged with one end on a base 41. In the exemplary embodiment, the base 41 stands on the surface 12. This is advantageous if vibrations could be coupled into the machine tool 10 or the machine bed 11 due to the mass, the forces and the accelerations when moving the robot arm. If such coupling of vibrations into the machine bed 11 is not critical due to the design and control of the movement of the robot arm 40, the robot arm 40 could also be attached to the machine bed 11 or another part of the machine tool 10.

Starting from the base 41, the robot arm 40 extends to a free end 42. At the free end 42, the robot arm 40 has a tool holder 43 for different tools 44. The tool holder 43 can be a standard interface, such as a tool holder 43 designed to hold hollow shaft cones (HSK).

Between the tool holder 43 and the base 41, the robot arm 40 has a plurality of links 45, with two adjacent links 45 being connected to one another in a rotatable or pivotable manner. The robot arm 40 has several robot axes R, each of which represents a degree of freedom in the movement or positioning of the free end 42 and therefore a tool 44 held in the tool holder 43 in space and, for example, at the setup station 25. At the in 1 In the robot arm 40 illustrated by way of example, there are six robot axes R, each of which forms a rotation or pivot axis for moving the respective link 45 relative to the adjacent link 45 or the base 41. The movement and positioning of the links 45 around the robot axes R is carried out by appropriately controllable robot axis drives. The free end 42 can therefore be moved, positioned and aligned in space relative to the base 41.

In one exemplary embodiment, the number of degrees of freedom in which the free end 42 of the robot arm 40 can be moved or positioned can be greater than the number of degrees of freedom with which the at least one tool spindle 16, and thus the machining tool 17, relative to the workpiece 14 is movable and positionable.

The robot arm 40 can process a workpiece 14 arranged at the setup station in the workpiece holder 28 during the main time, i.e. during the processing of a workpiece 14 by the at least one tool spindle 16 in the work space 13. Machining is understood to mean machining and/or non-machining machining, testing or measurement or any other activity that the robot arm 40 can carry out on the workpiece 14 using a tool 44. For example, the robot arm 40 can measure at least one dimension of the workpiece 14, mark a workpiece 14, for example using a laser, clean a workpiece 14, for example using a fluid such as compressed air or a Rinsing liquid, or machining a workpiece 14, for example by drilling or milling or the like.

Using a tool for additive manufacturing, for example a laser welding head 51, the robot arm 40 can also apply material to the workpiece 14 and connect it to the workpiece 14 in a materially bonded manner. For this purpose, appropriate material, in particular metallic material or plastic material, can be supplied to the tool 44. At the setup station there is a laser source 52 and a material feed 53 for feeding the material to be applied to the laser welding head 51. The laser source 52 and the material supply 53 are preferably arranged close to the workpiece holder 28 in order to be able to make the supply lines as short as possible.

If the robot arm 40 is set up at the setup station 25 for the additive application of material to the workpiece 14, the number of variants of a base part, for example a cast part, can be reduced. It is possible to cast a casting identically for several workpiece variants and/or to shape or produce it using other methods and to produce different characteristics of the variants at least through the additive application of material. This allows tool costs to be saved, especially for the casting tool.

The robot arm 40 can, for example, be set up to remove one or more burrs on the workpiece 14 that were caused by a previous work step. The robot arm 40 can optionally also be set up to clean the setup station 25 or parts thereof, for example the workpiece holder 28 or the workpiece 14. This allows chips or coolant residues to be removed in order to enable the workpiece 14 to be arranged in the workpiece holder 28 as precisely as possible .

At the setup station 25, a tool magazine 46 with several tools 44 for the robot arm 40 can be arranged within the machine outer wall 27. The tool magazine 46 is preferably arranged immovably at the setup station 25. The robot arm 40 is set up to pick up a tool 44 from the tool magazine 46 or to store a tool 44 arranged in the tool holder 43 in the tool magazine 46. This makes it possible to carry out different processing operations during the main time at set-up station 25. Depending on the task to be performed, the robot arm can accommodate the appropriate tool 44, for example a blowing nozzle or a rinsing nozzle for cleaning, a laser tool for marking a workpiece, a rotary tool that can be used for material removal, a measuring or testing tool, etc.

The robot arm 40 and the workflow in the work space 13 are controlled by the common control device 18. The entire machine tool 10 including the robot arm 40 is supplied with electrical energy and optionally other required fluids via a common supply 47, such as coolant and/or lubricants and/or compressed air and/or hydraulic fluid. Since the supply 47 for the machine tool 10 and the machining of the workpiece 14 is already present in the work space 13, the supply 47 can also be used at the same time for the set-up station 25 and in particular the workpiece holder 28 and the robot arm 40 with little effort. The installation area required by the machine tool 10 is only slightly increased compared to an embodiment of the machine tool 10 without a robot arm 40. In contrast, the efficiency of the machine tool 10 is significantly increased, since 25 work steps can be carried out by the robot arm 40 during the main time at the setup station, for which a highly precise and powerful tool spindle 16 is not necessarily required. As a result, the valuable main time can be reserved for work on the workpiece 14, which requires high accuracy and/or a high material removal rate. Less complex tasks with lower accuracy requirements, such as deburring, cleaning, cutting threads, etc., can be carried out during main time parallel to the machining of a workpiece 14 in the work area 13 on another workpiece 14 at the setup station 25.

At least one of the tools 44 for the robot arm 40 can be designed as a measuring tool 44a. The robot arm 40 can pick up the measuring tool 44a, and after placing a pallet 29 with a workpiece 14 in the workpiece holder 28, the robot arm 40 can measure one or more locations on the pallet 29 and / or the workpiece 14 in a contact or non-contact manner to determine the position and/or orientation of the workpiece 14 in a coordinate system of the robot arm 40. The workpiece 14 can then be processed at the setup station 25. This allows the accuracy when machining a workpiece 14 at the setup station 25 to be increased using the robot arm 40.

As it is highly schematized in the 2 and 3 is illustrated, the machine tool 10 has a removal device 48 with a removal channel 49 for chips and/or coolant residues. The removal device 48 is set up to remove both chips and/or coolant at the setup station 25, as well as in the workspace 13. This means that there is a uniform, shared removal of material residues or coolant residues. If dust and/or gases arise during processing, a common suction device 50 can be assigned to both the setup station 25 and the work space 13 in order to suck out such dusts or gases.

At least some of the functions F implemented in the control device 18 can be used to control and/or monitor the operation of the robot arm 40. This particularly applies to safety functions for ensuring occupational safety at the setup station. For example, the control device 18 can be set up to query a sensor signal U of at least one sensor 55, which characterizes a state of the machine tool 10. For example, the sensor 55 can be assigned to a flap or door on the workpiece transport opening 35 and transmit its status to the control device 18 using the sensor signal U. When the workpiece transport opening 25 is open, the movement of the robot arm 40 and/or the workpiece holder 28 and the processing of the workpiece 14 using the tool 44 of the robot arm 40 can be stopped or prevented. During the processing of the workpiece 14 at the setup station 25 or the movement of the workpiece holder 28 or the robot arm 40, for example, a door or flap on the workpiece transport opening 35 can be locked by the control device 18. Analogously to this, other access openings in the area encompassed by the machine outer wall 27, i.e. the work area 13 and the setup station 25, can also be monitored and secured.

The at least one higher-level function F can also be a function to ensure freedom from collisions. Such a function F is available anyway for the machine parts that can be moved by means of the at least one machine axis 19 and can also be used for the movement of the workpiece holder 28 or the movement of the robot arm 40.

In addition, the control device 18 can provide a higher-level function F, which specifies the movement coordinates and/or trajectory for moving the tool 44 by means of the robot arm 40 and/or the speed of the movement and/or the orientation of the tool 44. The control of the robot axle drives for moving the individual links 45 can also be taken over by the control device 18, whereby the control of the individual robot axle drives can also be carried out by a separate robot control unit 56, which, so to speak, carries out a subordinate control or regulation of the robot arm 40.

The invention relates to a machine tool 10 and a method for operating it. The machine tool 10 has a working space 13 with at least one tool spindle 16 and a clamping device 15 for a workpiece 14. In the workspace 13, a workpiece 14 can be processed during a main time. Separated from the work space 13 by a partition 26, there is a setup station 25 with a workpiece holder 28 immediately adjacent. Workpieces 14 can be transported between the workspace 13 and the setup station 25 via a workpiece changing device 33. A robot arm 40 is arranged at the setup station 25 and can process a workpiece present at the setup station 25 during main time. The work space 13, the setup station 25 and the robot arm 40 are preferably enclosed by a common outer machine outer wall 27. The robot arm 40 and machine axes 19 in the work area 13 are controlled by a common control device 18 of the machine tool 10.

List of reference symbols:

10

machine tool

11

Machine bed

12

underground

13

working space

14

workpiece

15

Clamping device

16

tool spindle

17

Editing tool

18

Control device

19

Machine axis

20

Workspace tool magazine

25

Preparation area

26

partition wall

26a

Partition section

27

Machine outer wall

28

Workpiece holder

29

palette

33

Workpiece changing device

34

Pallet gripper

35

Workpiece transport opening

40

Robot arm

41

base

42

free end of the robot arm

43

Tool holder

44

Tool

44a

Measuring tool

45

element

46

Tool magazine

47

care

48

removal facility

49

discharge channel

50

Suction device

51

Laser welding head

52

Laser source

53

Material supply

55

sensor

56

Robot control unit

D

Axis of rotation

F

higher-level function

R

Robot axis

S

Pivot axis

U

Sensor signal

Claims (18)

Machine tool (10) with several machine axes (19), with a work space (13) which is set up for machining a workpiece (14), in which a clamping device (15) for clamping the workpiece (14) during machining and a tool spindle (16) for receiving a machining tool (17) are arranged , wherein the tool spindle (16) and the clamping device (15) can be moved relative to one another by means of one or more of the machine axes (19), with a control device (18) which is set up to control the workflow of workpiece processing in the work area (13) during a main time, with a setup station (25) which is separated from the work area (13) by a partition (26), a workpiece holder (28) for holding the workpiece (14) being arranged at the setup station (25), with a workpiece changing device (33) which is arranged between the setup station (25) and the work space (13) and is set up to change a workpiece (14) between the setup station (25) and the work space (13), with a robot arm (40) assigned to the setup station (25) which can be moved in several degrees of freedom and which has a tool holder (43) at its free end (42) and which is set up to be in the workpiece holder at the setup station (25) during the main time (28) to process the workpiece (14) held, at least some of the functions implemented in the control device (18) also being used for controlling and / or monitoring the workflow at the setup station (25). machine tool Claim 1 , characterized in that the workpiece changing device (33) is set up to transport a machined workpiece (14) located in the workspace (13) out of the workspace (13). machine tool Claim 2 , characterized in that the workpiece changing device (33) is set up to transport the processed workpiece located in the work area (13) back to the set-up area (25) and at the same time to transport a prepared workpiece (14) from the set-up area to the work area (13). transport. Machine tool according to one of the preceding claims, characterized in that at least one partition section (26a) of the partition (26) is connected to the workpiece changing device (33). Machine tool according to one of the preceding claims, characterized in that the workpieces (14) are each fastened on a pallet (29), and in that the workpiece changing device (33) has at least one pallet gripper (34) which is set up to transport the workpieces (14) to attack the pallet (29). Machine tool according to one of the preceding claims, characterized in that the robot arm (40) is arranged on a base (41) adjacent to the machine bed (11) on a base (12). Machine tool according to one of the preceding claims, characterized in that the number of degrees of freedom in which the free end (42) of the robot arm (40) is movable is greater than the number of degrees of freedom in which the arm clamped in the clamping device (15). Workpiece (14) and the at least one tool spindle (16) can be moved relative to one another in the working space. Machine tool according to one of the preceding claims, characterized in that the tool holder (28) of the robot arm (40) has a standard interface for interchangeable tools (44). Machine tool according to one of the preceding claims, characterized in that a tool magazine (46) with several tools (44) for the robot arm (40) is arranged at the set-up station (25). Machine tool according to one of the preceding claims, characterized in that an outer machine wall (27) surrounds the working space (13) and the set-up area (25). machine tool Claim 10 , characterized in that there is a workpiece transport opening (35) in the machine outer wall (27) for the transport of workpieces (14) to and/or from the setup station (25). machine tool Claim 10 or 11 , characterized in that the work space (13) has an opening or is open at its top to enable the transport of workpieces (14) directly into or directly from the work space (13). Machine tool according to one of the preceding claims, characterized in that the robot arm (40) has or can accommodate a measuring tool (44a). machine tool Claim 13 , characterized in that the control device (18) is set up to control the robot arm (40) with the measuring tool (44a) in order to determine the position and/or orientation of the workpiece (25) arranged in the workpiece holder (28) at the setup station (25). 14) to be determined in a coordinate system of the robot arm (40). Machine tool according to one of the preceding claims, characterized in that the setup station (25) and the working space (13) have a common removal device (48) for chips and/or coolant. Method for operating a machine tool (10) according to one of the preceding claims with the following steps: - Transporting a workpiece (14) from the setup station (25) to the work area (13) and transporting another workpiece (14) to the setup station (25), - processing the workpiece (14) in the work area (13) during a main time, - Processing of the workpiece (14) arranged at the setup station (25) during main time by the robot arm (40). Procedure according to Claim 16 , characterized in that using the robot arm (40) at the setup station (25) material is applied to a workpiece (14) held in the workpiece holder (28) by an additive manufacturing process, the workpiece (14) being applied before and/or afterwards in the Workspace (13) has been or is being processed. Procedure according to Claim 17 , characterized in that to produce a predetermined workpiece variant from a group of possible workpiece variants, a base body is first produced as a workpiece (14), which is used for several or all workpiece variants, and that on the set-up station (25) in the workpiece holder (28 ) held base body material is applied by the additive manufacturing process in order to produce the selected, specified workpiece variant.

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