machine tool

Abstract

machine tool (1) comprising: a machine frame (2) in which a loading area (45) and a processing area (44) are formed; a first work spindle (5) which is rotatably mounted about a first spindle axis (7), wherein the first work spindle (5) is slidably mounted on the machine frame (2) along a horizontal Z-axis (9), along a horizontal X-axis (10) and along a vertical Y-axis (11); a workpiece clamping device (18) which is designed to hold at least one first workpiece (25) and one second workpiece (31), wherein a second work spindle (6) is formed which is rotatably mounted about a second spindle axis (8), wherein the second work spindle (6) is slidably mounted on the machine frame (2) along the Z-axis (9), along the X-axis (10) and along the Y-axis (11), wherein the first work spindle (5) and the second work spindle (6) are arranged vertically one above the other and the first work spindle (5) is designed for machining the first workpiece (25) and the second work spindle (6) for machining the second workpiece (31), characterized by the fact that a first tool turret (64) is arranged laterally to the workpiece clamping device (18), which is designed to accommodate several machining tools (51), wherein the first work spindle (5) is displaceable to the first tool turret (64) so ​​that the machining tools (51) can be directly transferred from the first tool turret (64) to the first work spindle (5) and that A second tool turret (65) is arranged laterally to the workpiece clamping device (18), which is designed to receive several machining tools (51), wherein the second work spindle (6) is movable to the second tool turret (65), so that the machining tools (51) can be received directly from the second tool turret (65) into the second work spindle (6).

Description

[0001] The invention relates to a machine tool.

[0002] EP3659744A1 discloses a machine tool for machining workpieces, comprising a workpiece table which is mounted in a machine frame so as to be rotatable about a horizontal axis of rotation and which has a workpiece carrier on each of its two opposite table sides for receiving at least one workpiece, wherein one workpiece carrier is provided on a machining side and the other workpiece carrier is provided on a loading side, and wherein the machining-side workpiece carrier and the loading-side workpiece carrier are interchangeable by pivoting the workpiece table.Furthermore, it is provided that the two workpiece carriers each have a protruding support edge for setting up, in particular, plate-shaped workpieces and that the workpiece table is inclined relative to the vertical in its processing and loading position, so that the workpiece placed on the support edge on the loading side can lean against the loading side of the table.

[0003] The machine tool disclosed in EP3659744A1 has the disadvantage that it has low flexibility and also low efficiency.

[0004] The object of the present invention was to overcome the disadvantages of the prior art and to provide an improved machine tool.

[0005] This object is achieved by a device according to the claims.

[0006] The invention relates to a machine tool comprising: a machine frame in which a loading space and a processing space are formed; a first work spindle which is rotatably mounted about a first spindle axis, wherein the first work spindle is slidably mounted on the machine frame along a horizontal Z-axis, along a horizontal X-axis and along a vertical Y-axis; a workpiece clamping device which is designed to hold at least a first workpiece and a second workpiece.

[0007] Furthermore, a second work spindle is formed, which is rotatably mounted about a second spindle axis, wherein the second work spindle is slidably mounted on the machine frame along the Z-axis, along the X-axis and along the Y-axis, wherein the first work spindle and the second work spindle are arranged vertically one above the other and the first work spindle is designed to machine the first workpiece and the second work spindle is designed to machine the second workpiece.

[0008] The X-axis and the Z-axis can be arranged in a horizontal plane and aligned orthogonally to each other. The Y-axis can be aligned orthogonally to the X-axis and the Z-axis and arranged vertically. In particular, the Z-axis can be aligned parallel to the spindle axes or parallel to the non-pivoted spindle axes, provided the work spindles are designed to pivot about the Y-axis.

[0009] The machine tool according to the invention offers the advantage that workpieces can be machined easily and with high efficiency. Furthermore, the machine tool according to the invention offers a high degree of flexibility for machining complex workpieces.

[0010] Furthermore, it may be expedient for the first work spindle and the second work spindle to be mounted on a common spindle adjustment device and to be movable together along the Z-axis. This offers the advantage that the first work spindle and the second work spindle can be moved using a common drive. This can simplify the design of the machine tool.

[0011] Alternatively, it can be provided that the first work spindle is displaceable in the Z-axis by means of a first spindle adjustment device and that the second work spindle is displaceable in the Z-axis by means of a second spindle adjustment device, wherein the first work spindle and the second work spindle each have their own adjustment drive and can be displaced independently of one another in the Z-axis. This has the advantage that the first work spindle and the second work spindle can perform machining operations independent of one another. In particular, two differently designed workpieces can thus be machined simultaneously in the machine tool. Furthermore, this measure can be used to compensate for tolerances in the different workpieces or in the workpiece tables.

[0012] Furthermore, it may be advantageous if the first work spindle and the second work spindle are mounted on a common Y-adjustment device and can be moved together along the Y-axis. This offers the advantage that the first work spindle and the second work spindle can be moved using a common drive. This can simplify the design of the machine tool.

[0013] Alternatively, it can be provided that the first work spindle is displaceable in the Y-axis by means of a first Y-adjustment device and that the second work spindle is displaceable in the Y-axis by means of a second Y-adjustment device, wherein the first work spindle and the second work spindle each have their own adjustment drive and can be displaced independently of one another in the Y-axis. This has the advantage that the first work spindle and the second work spindle can perform machining operations independent of one another. In particular, two differently designed workpieces can thus be machined simultaneously in the machine tool. Furthermore, this measure can be used to compensate for tolerances in the different workpieces or in the workpiece tables.

[0014] Furthermore, it may be advantageous if the first work spindle and the second work spindle are mounted on a common X-axis adjustment device and can be moved together along the X-axis. This offers the advantage that the first work spindle and the second work spindle can be moved using a common drive. This simplifies the design of the machine tool.

[0015] Alternatively, it can be provided that the first work spindle is displaceable along the X-axis by means of a first X-adjustment device, and that the second work spindle is displaceable along the X-axis by means of a second X-adjustment device, wherein the first work spindle and the second work spindle each have their own adjustment drive and can be displaced along the X-axis independently of one another. This offers the advantage that the first work spindle and the second work spindle can perform machining operations independently of one another. In particular, two differently shaped workpieces can thus be machined simultaneously in the machine tool.

[0016] The adjustability of the work spindles in the individual axes can be combined as desired.

[0017] Furthermore, it can be provided that, in addition to the first work spindle and the second work spindle, a third work spindle or even further work spindles are formed, wherein the first work spindle, the second work spindle, and the third work spindle are arranged vertically one above the other. This has the advantage of further increasing the efficiency of the machine tool.

[0018] Furthermore, it may be expedient if a swivel table is formed, wherein the swivel table a first front workpiece holder for directly and immovably receiving the first workpiece on the swivel table and a second front workpiece holder for directly and immovably receiving the second workpiece on the swivel table, and a first rear workpiece holder for directly and immovably receiving a first rear workpiece on the swivel table and a second rear workpiece holder for directly and immovably receiving a second rear workpiece on the swivel table, wherein the swivel table is pivotally mounted about a swivel table axis which is aligned parallel to a horizontal X-axis, wherein, depending on the pivot position of the swivel table, the first front workpiece holder and the second front workpiece holder can be pivoted into the machining space or the first rear workpiece holder and the second rear workpiece holder can be pivoted into the machining space. This has the advantage that the efficiency of the machine tool can be increased by this measure. At the same time, the structure of the machine tool can be kept as simple as possible. In particular, it can be provided that the swivel table can only be pivoted about the swivel table axis and is otherwise not displaceable relative to the machine frame.

[0019] In other words, the swivel table may have a swivel table front side on which the first front workpiece holder and the second front workpiece holder are arranged and a swivel table rear side on which the first rear workpiece holder and the second rear workpiece holder are arranged.

[0020] In other words, depending on the swivel position of the swivel table, the first work spindle can be assigned to the first front workpiece holder and the second work spindle to the second front workpiece holder, or the first work spindle can be assigned to the first rear workpiece holder and the second work spindle to the second rear workpiece holder. This has the advantage of increasing the efficiency of the machine tool.

[0021] Of course, it is also conceivable that in other swivel positions a further assignment of the workpiece holders to the machining area or to the work spindles is possible.

[0022] Furthermore, it can be provided that the first front workpiece holder is arranged at a first front workpiece holder distance from the swivel table axis, and that the second rear workpiece holder is arranged at a second rear workpiece holder distance from the swivel table axis, wherein the first front workpiece holder distance and the second rear workpiece holder distance are of different sizes, and wherein the swivel table has recesses through which a machining tool can be passed. This has the advantage that this measure also allows a side of the workpieces assigned to the swivel table to be machined.

[0023] Alternatively, the workpieces can be machined on their front side in a first clamping setup and on their back side in a second clamping setup. Re-clamping can take place parallel to machining time.

[0024] The swivel table can be swiveled around the swivel table axis using a swivel table drive motor.

[0025] In an alternative embodiment, it can be provided that the workpiece clamping device comprises a first workpiece table and a second workpiece table, wherein the first workpiece table is pivotably mounted about a first pivot axis which is aligned parallel to the X-axis, and the second workpiece table is pivotably mounted about a second pivot axis which is aligned parallel to the X-axis, and the first work spindle is assigned to the first workpiece table and the second work spindle is assigned to the second workpiece table, wherein the first workpiece table has a first front workpiece holder and a first rear workpiece holder, and the second workpiece table has a second front workpiece holder and a second rear workpiece holder, wherein depending on the pivot position of the first workpiece table and the second workpiece table,The first front workpiece holder and the second front workpiece holder can be pivoted into the machining area, or the first rear workpiece holder and the second rear workpiece holder can be pivoted into the machining area. This has the advantage of increasing the efficiency of the machine tool. At the same time, this measure can increase the flexibility of the machine tool.

[0026] In particular, it can be provided that the first workpiece table is pivotable exclusively about the first pivot axis and is otherwise not displaceable relative to the machine frame.

[0027] In particular, it can be provided that the second workpiece table is pivotable exclusively about the second pivot axis and is otherwise not displaceable relative to the machine frame.

[0028] In other words, the first workpiece table can have a first workpiece table front side, on which the first front workpiece holder is arranged. Furthermore, the second workpiece table can have a second workpiece table front side, on which the second front workpiece holder is arranged. Furthermore, the first workpiece table can have a first workpiece table rear side, on which the first rear workpiece holder is arranged. Furthermore, the second workpiece table can have a second workpiece table rear side, on which the second rear workpiece holder is arranged.

[0029] In a first embodiment, the first workpiece table and the second workpiece table may have a common drive unit for rotating the first workpiece table about the first pivot axis and for rotating the second workpiece table about the second pivot axis. The first workpiece table and the second workpiece table may be coupled to each other by means of a gear mechanism. This has the advantage of increasing the efficiency of the machine tool.

[0030] In a second embodiment, the first workpiece table may have a first drive unit for rotating the first workpiece table about the first pivot axis, and the second workpiece table may have a second drive unit for rotating the second workpiece table about the second pivot axis. The first workpiece table and the second workpiece table can be pivoted independently of one another. This has the advantage that this measure can increase the efficiency of the machine tool. At the same time, this measure can increase the flexibility of the machine tool.

[0031] In other words, depending on the swivel position of the first workpiece table, the first work spindle can be assigned to the first front workpiece holder or the first work spindle can be assigned to the first rear workpiece holder. Depending on the swivel position of the second workpiece table, the second work spindle can be assigned to the second front workpiece holder or the second rear workpiece holder. This has the advantage of increasing the efficiency of the machine tool. Furthermore, this measure allows the space requirements or installation space of the machine tool to be kept as small as possible.

[0032] Of course, it is also conceivable that in other swivel positions a further assignment of the workpiece holders to the machining area or to the work spindles is possible.

[0033] Also advantageous is a configuration according to which it can be provided that the first front workpiece holder is arranged at a first front workpiece holder distance from the first pivot axis and that the first rear workpiece holder is arranged at a first rear workpiece holder distance from the first pivot axis, wherein the first front workpiece holder distance and the first rear workpiece holder distance extend into different sides of the first workpiece table with respect to the first pivot axis and wherein the pivot table has recesses through which a machining tool can be passed. This has the advantage that this measure also allows a side of the workpieces assigned to the workpiece table to be machined.

[0034] According to a further development, it is possible for the first workpiece table to have a first radius which is adapted to a first flight circle of the first workpiece table, and for the second workpiece table to have a second radius which is adapted to a second flight circle of the second workpiece table, wherein the first flight circle of the first workpiece table and the second flight circle of the second workpiece table are arranged at a flight circle distance of between 0.1 mm and 10 mm, in particular between 0.2 mm and 5 mm, preferably between 0.5 mm and 2 mm, from one another. This has the advantage that the smallest possible gap can be created between the first workpiece table and the second workpiece table, so that the best possible separation can be created between the loading space and the processing space.

[0035] Furthermore, it can be provided that the first workpiece table has a first sealing element, in particular at the first radius, and the second workpiece table has a second sealing element, in particular at the second radius. This has the advantage that this measure can improve the seal between the first workpiece table and the second workpiece table.

[0036] In particular, it can be provided that the first radius extends over a certain area of ​​the first workpiece table or that the first workpiece table has a certain thickness, so that the sealing function can be maintained even with a slight pivoting of the first workpiece table.

[0037] Furthermore, it can be provided that the second radius extends over a certain area of ​​the second workpiece table or that the second workpiece table has a certain thickness, so that the sealing function can be maintained even with a slight pivoting of the second workpiece table.

[0038] Furthermore, a rubber profile can be arranged on the first radius and / or the second radius. This measure can further increase the sealing effect.

[0039] Furthermore, it can be provided that a sealing element, such as a rubber profile or a brush, is arranged on the first radius and / or on the second radius, which is displaceable in the radial direction in order to be able to adjust and / or actively close the gap.

[0040] In an alternative embodiment, it can be provided that the first workpiece table has a first flight circle of the first workpiece table and the second workpiece table has a second flight circle of the second workpiece table, wherein the first flight circle of the first workpiece table and the second flight circle of the second workpiece table are arranged at a flight circle distance from one another, wherein a partition wall segment is arranged between the first workpiece table and the second workpiece table, wherein the partition wall segment has a shape adapted to the first flight circle and the second flight circle. This has the advantage that this measure can create the best possible separation between the loading area and the processing area. Furthermore, this measure can be used to vary the distance between the two workpiece tables without having to change the size of the two workpiece tables.

[0041] In particular, it can be provided that the separation has a shape that is negative to the first radius or the second radius and has a certain thickness, so that the sealing function can be maintained even with a slight pivoting of the first workpiece table or the second workpiece table.

[0042] Furthermore, it can be provided that a first tool magazine is arranged laterally to the workpiece clamping device or at a longitudinal end of the workpiece clamping device, which first tool magazine is designed to accommodate a plurality of machining tools, wherein the first work spindle is displaceable to the first tool magazine, so that the machining tools can be accommodated directly from the first tool magazine into the first work spindle and that a second tool magazine is arranged laterally to the workpiece clamping device, which is designed to accommodate a plurality of machining tools, wherein the second work spindle is displaceable towards the second tool magazine so that the machining tools can be received directly from the second tool magazine into the second work spindle.

[0043] Furthermore, it can be provided that a first tool turret is arranged laterally to the workpiece clamping device or at a longitudinal end of the workpiece clamping device, which is designed to accommodate a plurality of machining tools, wherein the first work spindle is displaceable to the first tool turret, so that the machining tools can be accommodated directly from the first tool turret into the first work spindle and that a second tool turret is arranged laterally to the workpiece clamping device, which is designed to accommodate a plurality of machining tools, wherein the second work spindle can be moved towards the second tool turret so that the machining tools can be picked up directly from the second tool turret into the second work spindle. This has the advantage that this measure can achieve the simplest possible tool change. In particular, it can be provided that the tool turrets can each rotate the machining tools into a change position in which the machining tools can be removed from the respective work spindle or machining tools that are currently in use can be inserted into the tool turret.In particular, it is conceivable for the work spindles to be able to move to multiple positions of the respective tool turret, so that the currently used machining tool can be deposited and the new machining tool can be removed without rotating the tool turret. In particular, it can be provided that the first tool turret is positioned such that two tool holding positions of the first tool turret are arranged vertically one above the other, so that the old tool of the first work spindle can be deposited and a new tool of the first work spindle can be picked up without rotating the first tool turret and without shifting the first work spindle in the X-axis.Furthermore, it can be provided that the second tool turret is positioned such that two tool receiving locations of the second tool turret are arranged vertically one above the other, so that the old tool of the second work spindle can be deposited and a new tool can be picked up without rotating the second tool turret and without shifting the second work spindle in the X-axis.

[0044] Of course, it is also conceivable that between the setting down of the currently used machining tool and the removal of the new machining tool, both the respective machining spindle is moved and the respective tool turret is rotated. The individual tool holding positions can be arranged in a circular pattern on the tool turret.

[0045] Furthermore, it can be provided that two tool turrets are also arranged on a second side of the workpiece clamping device or on a second longitudinal end of the workpiece clamping device, which tool turrets have a similar structure to the first tool turret and second tool turret already described.

[0046] In an alternative, a tool magazine can be arranged at a longitudinal end of the workpiece clamping device, wherein the tool magazine comprises a chain-type magazine, wherein a straight run of the chain-type magazine is vertically aligned, wherein the first work spindle and the second work spindle are displaceable relative to the straight run of the chain-type magazine, wherein a distance between the first work spindle and the second work spindle corresponds to a pitch or a multiple of the pitch of the chain-type magazine. It is advantageous here that the first work spindle and the second work spindle can be moved relative to the chain-type magazine in order to deposit the no longer required work tool and to accommodate a new machining tool.Because the distance between the first work spindle and the second work spindle corresponds to a pitch or a multiple of a pitch of the chain circulating magazine, the machining tools held in the first work spindle and second work spindle can be deposited at the same time or new machining tools can be picked up at the same time in a wider step.

[0047] Furthermore, it may be advantageous for the first work spindle and the second work spindle to be movable independently of each other along the horizontal Z-axis and the vertical Y-axis. This offers the advantage that the workpieces can be machined efficiently even when the work tables are tilted. This also offers the advantage that the first and second workpieces can have different shapes.

[0048] Furthermore, it can be provided that a first swivel head is formed, by means of which the first work spindle can be pivoted about the vertical Y-axis, and that a second swivel head is formed, by means of which the second work spindle can be pivoted about the vertical Y-axis. In particular, it can be provided that the first work spindle can be pivoted exclusively about the vertical Y-axis and cannot otherwise be pivoted about any axis, and that the second work spindle can be pivoted exclusively about the vertical Y-axis and cannot otherwise be pivoted about any axis. This measure can further increase the flexibility of the machine tool while keeping its complexity as low as possible.

[0049] Furthermore, a method for operating a machine tool may be provided. The method comprises the following steps: - machining a first workpiece, which is clamped on a first front workpiece holder of the workpiece clamping device and is pivoted into a machining space of the machine tool, by means of a machining tool clamped in the first work spindle and simultaneously loading a first rear workpiece on a first rear workpiece holder of the workpiece clamping device, wherein the first rear workpiece holder is pivoted into a loading space of the machine tool; - alternating machining of the first workpiece and the first rear workpiece by means of the same machining tool clamped in the first work spindle, wherein the first front workpiece holder of the workpiece clamping device or the first rear workpiece holder of the workpiece clamping device is pivoted into the machining space of the machine tool in a pendulum operation.

[0050] The process has the advantage that the efficiency of the machine tool can be improved.

[0051] In one embodiment, it is possible for the method to be carried out by means of a machine tool, comprising: a machine frame in which a loading space and a processing space are formed; a first work spindle which is rotatably mounted about a first spindle axis, wherein the first work spindle is slidably mounted on the machine frame along a horizontal Z-axis, along a horizontal X-axis and along a vertical Y-axis; a workpiece clamping device which is designed to receive a first workpiece and a first rear workpiece. Wherein a swivel table is formed, wherein the swivel table a first front workpiece holder for the direct and immovable holding of the first workpiece on the swivel table and a first rear workpiece holder for the direct and immovable reception of a first rear workpiece on the swivel table, wherein the swivel table is pivotally mounted about a swivel table axis which is aligned parallel to a horizontal X-axis, wherein, depending on the swivel position of the swivel table, the first front workpiece holder can be pivoted into the machining space or the first rear workpiece holder can be pivoted into the machining space.

[0052] In a further embodiment, it is possible for the method to be carried out by means of a machine tool, comprising: a machine frame in which a loading space and a processing space are formed; a first work spindle which is rotatably mounted about a first spindle axis, wherein the first work spindle is slidably mounted on the machine frame along a horizontal Z-axis, along a horizontal X-axis and along a vertical Y-axis; a workpiece clamping device which is designed to hold at least one first

[0053] workpiece and a second workpiece.

[0054] Furthermore, a second work spindle is formed, which is rotatably mounted about a second spindle axis, wherein the second work spindle is slidably mounted on the machine frame along the Z-axis, along the X-axis and along the Y-axis, wherein the first work spindle and the second work spindle are arranged vertically one above the other and the first work spindle is designed to machine the first workpiece and the second work spindle is designed to machine the second workpiece. Wherein a swivel table is formed, wherein the swivel table a first front workpiece holder for directly and immovably receiving the first workpiece on the swivel table and a second front workpiece holder for directly and immovably receiving the second workpiece on the swivel table, and a first rear workpiece holder for directly and immovably receiving a first rear workpiece on the swivel table and a second rear workpiece holder for directly and immovably receiving a second rear workpiece on the swivel table, The swivel table is pivotally mounted about a swivel table axis aligned parallel to a horizontal X-axis, and depending on the swivel position of the swivel table, the first front workpiece holder and the second front workpiece holder can be pivoted into the machining space, or the first rear workpiece holder and the second rear workpiece holder can be pivoted into the machining space. In this case, the method can additionally comprise the following method steps: - machining a second workpiece, which is clamped on a second front workpiece holder of the workpiece clamping device and is pivoted into a machining space of the machine tool, by means of a machining tool clamped in the second work spindle and simultaneously loading a second rear workpiece on a second rear workpiece holder of the workpiece clamping device, wherein the second rear workpiece holder is pivoted into a loading space of the machine tool; - alternating machining of the second workpiece and the second rear workpiece by means of the same machining tool clamped in the second work spindle, wherein the second front workpiece holder of the workpiece clamping device or the second rear workpiece holder of the workpiece clamping device is pivoted into the machining space of the machine tool in a pendulum operation.

[0055] Also advantageous is a configuration according to which it can be provided that the loading of the first rear workpiece at the first rear workpiece holder of the workpiece clamping device takes place within a time window in which the machining of the first workpiece does not require pivoting of the first front workpiece holder. Outside of this time window, during machining of the first workpiece, the first workpiece table is pivoted about a first pivot axis, or the pivot table is pivoted about the pivot table axis. This measure makes it possible for the first workpiece to be pivoted for more flexible machining, and a corresponding time window is used for changing the first rear workpiece.

[0056] In particular, it can be provided that the loading of the first rear workpiece into the first rear workpiece holder of the workpiece clamping device takes place during a time window in which the machining tool is not currently engaged with the workpiece. This can occur, for example, during a tool change or when the machining tool is repositioned relative to the workpiece in rapid traverse. This has the advantage that any impacts during the workpiece change do not lead to machining errors in the workpiece that is currently being machined.

[0057] In an alternative embodiment, it is also conceivable that the loading of the first rear workpiece at the first rear workpiece holder of the workpiece clamping device takes place parallel to the machining of the first workpiece, wherein during the machining of the first workpiece the first workpiece table is pivoted about a first pivot axis or the pivot table is pivoted about the pivot table axis, wherein A loading device for loading the first rear workpiece at the first rear workpiece holder according to the pivoting of the first workpiece table about the first pivot axis or of the pivot table about the pivot table axis, with the first rear workpiece pivoted accordingly to enable loading during the pivoting process. This may be necessary, especially for complex workpieces that require continuous pivoting of the workpiece.

[0058] In other words, it can be provided that the loading of the first rear workpiece on the first rear workpiece holder of the workpiece clamping device takes place in a time window in which the first workpiece table is pivoted about a first pivot axis or the pivot table is pivoted about the pivot table axis, wherein a movement of a device for loading the first rear workpiece is synchronized with the movement of the first rear workpiece holder. This has the advantage that a workpiece change can take place even if there is no time window available in which the workpiece table or the pivot table is not pivoted. In particular, it can be provided that the first rear workpiece is placed on the first rear workpiece holder gently so that machining errors are kept as low as possible.In particular, it can be provided that the time window is selected in such a way that the machining carried out in parallel does not constitute a final machining of a surface, so that any machining errors caused by vibrations when loading the first rear workpiece are removed again in a later machining step.

[0059] According to a further development, it is possible for the program sequence for machining the first workpiece and the first rear workpiece to be analyzed using a digital computer, with the time window for loading the first rear workpiece being automatically determined by the digital computer. This has the advantage that the time window does not have to be determined by the programmer or machine operator. In particular, it can be provided that the digital computer performs an evaluation of the program sequence. The digital computer can have an optimization algorithm stored with which the time window for loading the first rear workpiece is calculated.

[0060] Furthermore, it may be expedient if, in one work step, the swivel table, with the first front workpiece holder and the first workpiece held thereon and the second front workpiece holder and the second workpiece held thereon as well as with the first rear workpiece holder and the first rear workpiece held thereon and the second rear workpiece holder and the second rear workpiece held thereon, is tilted around the swivel table axis at an angle between 45° and 135°, in particular by 90° to a vertical position, whereby the first workpiece is machined by the second work spindle and the second rear workpiece is machined by the first work spindle. This has the advantage that this measure enables machining of a lateral surface of the first workpiece or the second rear workpiece with respect to the workpiece clamping.

[0061] In addition, it can be provided that in one work step the swivel table, with the first front workpiece holder and the first workpiece held thereon and the second front workpiece holder and the second workpiece held thereon tilted around the swivel table axis at an angle between 0.5° and 70° relative to a vertical position, with the first workpiece being machined simultaneously by the first work spindle and the second workpiece being machined by the second work spindle. The first work spindle and the second work spindle are positioned in different positions along the horizontal Z-axis so that the tilting of the swivel table is compensated. This may be necessary to be able to machine both workpieces simultaneously with a tilted swivel table.

[0062] Furthermore, it may be expedient if the first workpiece held in the first front workpiece holder and the second workpiece held in the second front workpiece holder are mirror-symmetrical, with the first work spindle and the second work spindle being adjusted in the vertical Y-axis in a mirror-symmetrical manner. This allows, for example, left and right components for vehicles to be easily manufactured.

[0063] Furthermore, it can be provided that, during machining of the first workpiece, the first work spindle is pivoted about the vertical Y-axis by means of a first pivoting head. This has the advantage of further increasing the flexibility during machining of the first workpiece.

[0064] Furthermore, it can be provided that two different machining tools are clamped in the first work spindle and in the second work spindle, wherein both the first workpiece and the second workpiece are machined by means of the machining tool clamped in the first work spindle, and both the first workpiece and the second workpiece are machined by means of the machining tool clamped in the second work spindle. This has the advantage that this measure can increase the efficiency of the machine tool, since the non-productive times for changing the machining tools can be eliminated. In this case, it can be provided that the first work spindle and the second work spindle carry out machining on the first workpiece at the same time and, at a later time, carry out machining on the second workpiece at the same time.Alternatively, it can be provided that the first work spindle performs machining on the first workpiece, while the second work spindle simultaneously performs machining on the second workpiece. At a later point in time, the second work spindle performs machining on the first workpiece, while the first work spindle simultaneously performs machining on the second workpiece. Of course, this requires that the work spindles can be moved along the Y-axis a sufficient distance to perform such machining.

[0065] This measure is particularly useful when the machining steps with the different machining tools take approximately the same amount of time. This could be, for example, drilling a hole using a drilling tool clamped in the first work spindle and cutting a thread or countersinking using a thread cutter or countersinking tool clamped in the second work spindle.

[0066] A machining tool within the meaning of this document can, for example, be a cutting tool. A machining tool within the meaning of this document can also be, for example, a friction stir welding tool. In the broadest sense, a measuring or testing device mounted in the work spindle can also be considered a machining tool.

[0067] The machining area, as defined in this document, is the area within the machine tool where machining takes place. In particular, the machining area may be enclosed in an enclosure to minimize all emissions from the machining area.

[0068] The loading area within the meaning of this document is located on the side of the workpiece clamping device facing away from the machining area.

[0069] The loading area can also be enclosed by a housing. In particular, it can be provided that the machining area and the loading area are enclosed by a common housing, with the loading area being separated from the machining area by the workpiece clamping device. This concept is particularly applicable to fully automated machine tools, in which a handling device for clamping the workpieces is provided on the workpiece clamping device.

[0070] In an alternative design, it is also conceivable for the loading area to be freely accessible and not enclosed. In such machine tools, the workpiece clamping device forms part of the machining area's enclosure.

[0071] For a better understanding of the invention, it is explained in more detail using the following figures.

[0072] They show in a highly simplified, schematic representation: Fig. 1 a perspective view of a first embodiment of a machine tool with a first workpiece table and a second workpiece table; Fig. 2 a schematic side view of an embodiment of the machine tool with a first workpiece table and a second workpiece table with radii; Fig. 3 a schematic side view of an embodiment of the machine tool with a first workpiece table and a second workpiece table with a partition wall segment; Fig. 4 a perspective view of another embodiment of the machine tool with a swivel table and a tool magazine; Fig. 5 a schematic side view of an embodiment of the machine tool with the swivel table and workpieces arranged offset from one another; Fig. 6 a schematic side view of an embodiment of the machine tool with the swivel table and workpieces arranged one behind the other, wherein the swivel table is swiveled by 90°; Fig. 7 a perspective rear view of another embodiment of the machine tool with two main adjustment units; Fig. 8 a plan view of an embodiment of a first work spindle with a first swivel head; Fig. 9 a plan view of an embodiment of a second work spindle with a second swivel head; Fig. 10 a schematic side view of an embodiment of the machine tool with the swivel table and a work spindle.

[0073] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0074] Fig. 1 shows a schematic representation of a machine tool 1 for machining workpieces 25, 31, 28, 34. The machine tool 1 has a machine frame 2, which serves as a base for the components attached to it.

[0075] The machine frame 2 is in Fig. 1 is shown only schematically for the sake of clarity. However, it should be noted that the machine frame 2 can be anchored at the installation site. Furthermore, the machine frame 2 can, of course, serve to accommodate all components of the machine tool 1.

[0076] Furthermore, a spindle adjustment device 3 is provided, which is arranged on the machine frame 2 or coupled thereto. The spindle adjustment device 3 can serve to accommodate a first work spindle 5 and a second work spindle 6.

[0077] The spindle adjustment device 3 can have a work head 4, on which a first work spindle 5 and a second work spindle 6 can be mounted. The first work spindle 5 is mounted on the work head 4 so as to be rotatable about a first spindle axis 7, and the second work spindle 6 is mounted on the work head 4 so as to be rotatable about a second spindle axis 8. The two work spindles 5, 6 each serve to hold a machining tool 51 and, for this purpose, have a clamping device for holding the machining tool 51.

[0078] The work spindles 5, 6 are adjustable relative to the machine frame 2 by means of the spindle adjustment device 3 in a Z-axis 9, in an X-axis 10 and in a Y-axis 11 arranged at right angles to the Z-axis 9 and X-axis 10.

[0079] In a further embodiment, it can be provided that the work spindles 5, 6 are mounted on the work head 4 so that they are immovable relative to one another, and thus only the work head 4 has to be moved in the Z-axis 9, in the X-axis 10 and in the Y-axis 11 relative to the machine frame 2 in order to move the work spindles 5, 6 synchronously with one another.

[0080] In particular, it can be provided that the Z-axis 9 is arranged horizontally. The first spindle axis 7 and the second spindle axis 8 can be arranged parallel to the Z-axis 9. Furthermore, it can be provided that the X-axis 10 is also arranged horizontally. The X-axis 10 is arranged at a right angle to the Z-axis 9.

[0081] The spindle adjustment device 3 can have a main adjustment unit 12, which is coupled to the machine frame 2 by means of an X-axis linear guide 13. For simplified illustration, the X-axis linear guide 13 is shown only rudimentarily. In particular, the X-axis linear guide 13 can have four or more guide carriages, which are coupled to the main adjustment unit 12 and which interact with two guide rails that are coupled to the machine frame 2.

[0082] The main adjustment unit 12 can be moved in the direction of the X-axis 10 relative to the machine frame 2 by means of the X-axis linear guide 13.

[0083] Furthermore, it can be provided that a height adjustment unit 14 is formed, which is coupled to the main adjustment unit 12 by means of a Y-axis linear guide 15. The Y-axis linear guide 15 enables the height adjustment unit 14 to be displaced along the Y-axis 11 relative to the main adjustment unit 12 or relative to the machine frame 2.

[0084] In a first embodiment, the first work spindle 5 is arranged on a first height adjustment unit 14 and the second work spindle 6 is arranged on a second height adjustment unit 14, and thus can be displaced independently of one another along a Y-axis 11. In this embodiment, the first height adjustment unit 14 can have a first drive and the second height adjustment unit 14 can have a second drive. Both height adjustment units 14 can be mounted on the main adjustment unit 12 by means of a Y-axis linear guide 15.

[0085] In a further embodiment, the first work spindle 5 and the second work spindle 6 can be arranged on a common height adjustment unit 14 and thus be displaceable together along a Y-axis 11. In this embodiment, only a single drive is required for the common height adjustment units 14.

[0086] The Y-axis linear guide 15 may also comprise a guide rail which is arranged on the main adjustment unit 12 and which is coupled to one or more guide carriages which are arranged on the first work spindle 5 or the second work spindle 6.

[0087] Furthermore, as can be seen from the illustration Fig. 1, it can be provided that the first work spindle 5 is displaceable in the Z-axis 9 by means of a first Z-axis linear guide 16 and that the second work spindle 6 is displaceable in the Z-axis 9 by means of a second Z-axis linear guide 17, wherein the first work spindle 5 and the second work spindle 6 are displaceable independently of one another. It can be provided that the first work spindle 5 is displaceable in the Z-axis 9 by means of a first drive and the second work spindle 6 is displaceable in the Z-axis 9 by means of a second drive.

[0088] In addition, the machine tool 1 comprises a workpiece clamping device 18, which serves to hold the workpieces 25, 31, 28, 34 to be machined.

[0089] The workpiece clamping device 18 can have a first workpiece table 19 and a second workpiece table 20. The first workpiece table 19 is pivotable relative to the machine frame 2 with respect to a first pivot axis 21. The second workpiece table 20 is pivotable relative to the machine frame 2 with respect to a second pivot axis 22.

[0090] The two swivel axes 21, 22 of the two workpiece tables 19, 20 are arranged parallel to the X-axis 10.

[0091] In particular, it can be provided that the first workpiece table 19 has a first front workpiece holder 24 for receiving the first workpiece 25 on a first workpiece table front side 23. Furthermore, it can be provided that the first workpiece table 19 has a first rear workpiece holder 27 for receiving a first rear workpiece 28 on a first workpiece table rear side 26.

[0092] Furthermore, it can be provided that the second workpiece table 20 has a second front workpiece holder 30 on a second workpiece table front side 29 for receiving the second workpiece 31. Furthermore, it can be provided that the second workpiece table 20 has a second rear workpiece holder 33 on a second workpiece table rear side 32 for receiving a second rear workpiece 34.

[0093] In particular, it can be provided that the first workpiece 25 and the second workpiece 31 are designed to be identical to one another in their outer contours and that the same machining steps are carried out on the two workpieces 25, 31. Furthermore, it can of course also be provided that the first workpiece 25 and the first rear workpiece 28 are designed to be identical to one another in their outer contours and that the same machining steps are carried out on the two workpieces 25, 28. Furthermore, it can of course also be provided that the second workpiece 31 and the second rear workpiece 34 are designed to be identical to one another in their outer contours and that the same machining steps are carried out on the two workpieces 31, 34.

[0094] For the sake of clarity, the two workpiece tables 19, 20 are Fig. 1 is only rudimentarily shown. Naturally, a wide variety of fastening options can be provided for attaching the workpieces 25, 31, 28, 34 to the workpiece tables 19, 20. In particular, it can be provided that rotary tables are formed on each of the two workpiece tables 19, 20, which serve to fasten the workpieces 25, 31 and simultaneously rotate the workpieces 25, 31, 28, 34 relative to the workpiece tables 19, 20.

[0095] The first workpiece table 19 is rotatably mounted on the machine frame 2 by means of a first pivot bearing 35 and a second pivot bearing 36. Similarly, the second workpiece table 20 is rotatably mounted on the machine frame 2 by means of a first pivot bearing 37 and a second pivot bearing 38. The pivot bearings 35, 36, 37, 38 can, for example, be designed in the form of bearing blocks, which are attached to corresponding receptacles on the workpiece table 19.

[0096] As from Fig. 1, it can be provided that the first workpiece table 19 has a workpiece clamping area which extends between the first pivot bearing 35 and the second pivot bearing 36. Analogously, it can be provided that the second workpiece table 20 has a workpiece clamping area which extends between the first pivot bearing 37 and the second pivot bearing 38 of the second workpiece table 20.

[0097] The workpiece clamping area of ​​the first workpiece table 19 has a first workpiece clamping length. The workpiece clamping area of ​​the second workpiece table 20 has a second workpiece clamping length. Preferably, the first workpiece table 19 and the second workpiece table 20 are of identical design.

[0098] The two workpiece tables 19, 20 and the two pivot axes 21, 22 are arranged at a distance 39 from each other. The distance 39 also extends in the direction of the Y-axis 11. The described configuration ensures that the first work spindle 5 is assigned to the first workpiece table 19 and that the second work spindle 6 is assigned to the second workpiece table 20.

[0099] In particular, it can be provided that an adjusting device is arranged in the workpiece clamping device 18, by means of which the distance 39 between the two workpiece tables 19, 20 or the two pivot axes 21, 22 can be adjusted.

[0100] By means of the machine tool 1 according to the invention, two workpieces 25, 31 of identical construction can be machined parallel to one another. The first workpiece 25 is clamped to the first workpiece table 19 and the second workpiece 31 to the second workpiece table 20. The tool of the first work spindle 5 machines the first workpiece 25, and the tool of the second work spindle 6 machines the second workpiece 31. Due to the inventive design of the machine tool 1, the machining of the first workpiece 25 and the second workpiece 31 can take place synchronously with one another. Thus, two workpieces 25, 31 can be machined simultaneously using a machine tool 1 with the simplest possible design, thereby improving the utilization of the machine tool 1 and its productivity.

[0101] Furthermore, parallel to the machining of the first workpiece 25, which is clamped on the first workpiece table front side 23, the first rear workpiece 28 can be exchanged on the first workpiece table rear side 26.

[0102] Furthermore, parallel to the machining of the second workpiece 31, which is clamped on the second workpiece table front side 29, the second rear workpiece 34 can be exchanged on the second workpiece table rear side 32.

[0103] Furthermore, it can be provided that the first workpiece table 19 has a first drive unit 40 for pivoting, and the second workpiece table 20 has a second drive unit 41 for pivoting. In such an embodiment, the first workpiece table 19 and the second workpiece table 20 can be pivoted independently of one another.

[0104] The first drive unit 40 and the second drive unit 41 can each be designed as a torque motor, for example.

[0105] It can be provided that the rotor of the torque motor is torque-coupled directly to the workpiece tables 19, 20.

[0106] In an alternative variant, it can be provided that the workpiece tables 19, 20 are pivoted by means of a common drive unit.

[0107] The common drive unit, in particular a torque motor, can be coupled to the two workpiece tables 19, 20, for example, by means of a belt drive. Alternatively, the common drive unit can be coupled to the two workpiece tables 19, 20 by means of a worm gear.

[0108] Furthermore, it can be provided that the two work spindles 5, 6 are driven by a common drive unit. The drive unit can, for example, be formed by a three-phase asynchronous motor controlled by a frequency converter.

[0109] Furthermore, it is also conceivable that the drive unit is designed in the form of a synchronous motor.

[0110] Of course, it is also possible for each of the work spindles 5, 6 to be driven by its own drive unit. In this case, the work spindle 5, 6 can also be the rotor of the drive unit.

[0111] Furthermore, it can be provided that a distance 42 between the first work spindle 5 and the second work spindle 6 is adjustable in the vertical Y-axis 11.

[0112] Furthermore, it can be provided that a digital computer 43 is formed, which can serve to control the machine tool 1.

[0113] As from Fig. As can also be seen in Figure 1, a machining space 44 can be formed in the area of ​​the work spindles 5, 6. The machining space 44 can be enclosed by a housing (not shown) or delimited by the first workpiece table 19 and the second workpiece table 20. A loading space 45 can be formed on the side of the first workpiece table 19 and the second workpiece table 20 opposite the machining space 44. A manipulation device for handling the workpieces 25, 31, 28, 34 can be arranged in the loading space 45.

[0114] In the Fig. 2 and Fig. 3 shows a schematic representation of further and possibly independent embodiments of the machine tool 1, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 1. To avoid unnecessary repetition, please refer to the detailed description in the previous Fig. 1. In particular, it is pointed out that the embodiment of those machine tools 1 which are described in the Fig. 2 and Fig. 3, the same features or at least partially the same features as that embodiment of the machine tool 1 which is shown in Fig. 1. For a better understanding, the Fig. 2 and Fig. 3 a highly schematically simplified representation has been chosen.

[0115] As from Fig. 2, it can be provided that the first workpiece table 19 has a first radius 46, which is adapted to a first flight circle 48 of the first workpiece table 19. The first radius 46 can form the end of the first workpiece table 19.

[0116] Furthermore, it can be provided that the second workpiece table 20 has a second radius 47, which is adapted to a second flight circle 49 of the second workpiece table 20. The second radius 47 can form the end of the second workpiece table 20.

[0117] Furthermore, it can be provided that the first flight circle 48 of the first workpiece table 19 and the second flight circle 49 of the second workpiece table 20 are arranged at a flight circle distance 50 of between 0.5 mm and 2 mm from one another in order to achieve the best possible seal between the first workpiece table 19 and the second workpiece table 20. This measure allows the machining chamber 44 and the loading chamber 45 to be separated from one another in order to prevent, as far as possible, the escape of chips or coolant from the machining chamber 44 into the loading chamber 45.

[0118] In Fig. 2, the machining tools 51 accommodated in the work spindles 5, 6 are also clearly visible.

[0119] As from Fig. 2, it can be provided that the first workpiece table 19 has a first sealing element 74 at the first radius 46. The first sealing element 74 is shown only on one side of the first workpiece table 19 to illustrate an embodiment with a first sealing element 74 and an embodiment without a first sealing element 74. However, it can expediently be provided that a first sealing element 74 is arranged on both sides of the first workpiece table 19, or that no first sealing element 74 is arranged.

[0120] Furthermore, it can be provided that the second workpiece table 20 has a second sealing element 75 at the second radius 47. The second sealing element 75 is shown only on one side of the second workpiece table 20 to illustrate an embodiment with a second sealing element 75 and an embodiment without a second sealing element 75. However, it can be expediently provided that a second sealing element 75 is arranged on both sides of the second workpiece table 20, or that no second sealing element 75 is arranged.

[0121] As further explained in Fig. As can be seen from Figure 3, the first workpiece table 19 can have a first radius 46, which is adapted to a first flight circle 48 of the first workpiece table 19. The first radius 46 can form the end of the first workpiece table 19.

[0122] The first sealing element 74 and the second sealing element 75 can of course also be used in the embodiment according to Fig. 3 should be provided.

[0123] Furthermore, it can be provided that the second workpiece table 20 has a second radius 47, which is adapted to a second flight circle 49 of the second workpiece table 20. The second radius 47 can form the end of the second workpiece table 20.

[0124] Furthermore, it can be provided that a partition wall segment 52 is arranged between the first workpiece table 19 and the second workpiece table 20, wherein the partition wall segment 52 has a shape adapted to the first flight circle 48 and the second flight circle 49. In particular, the partition wall segment 52 can have a first concave shape 53 towards the first workpiece table 19 and a second concave shape 54 towards the second workpiece table 20.

[0125] This allows for the best possible seal to be achieved between the first workpiece table 19 and the second workpiece table 20. This measure allows the machining chamber 44 and the loading chamber 45 to be separated from each other in order to prevent, as far as possible, the escape of chips or coolant from the machining chamber 44 into the loading chamber 45.

[0126] Of course, in both versions the Fig. 2 and Fig. 3, as can be seen from these, the housing of the machine tool 1 also has a concave shape adapted to the first workpiece table 19 or the second workpiece table 20.

[0127] As from Fig. 3, it can be provided that the first front workpiece holder 24 is arranged on the first workpiece table 19 at a first front workpiece holder distance 56 from the first pivot axis 21. Furthermore, it can be provided that the first rear workpiece holder 27 is arranged at a first rear workpiece holder distance 57 from the first pivot axis 21. In this case, it can be provided that the first front workpiece holder distance 56 and the first rear workpiece holder distance 57 extend into different sides of the first workpiece table 19 with respect to the first pivot axis 21. In particular, it can be provided that the first front workpiece holder distance 56 and the first rear workpiece holder distance 57 are the same size, so that the first front workpiece holder 24 and the first rear workpiece holder 27 are arranged symmetrically on the first workpiece table 19.

[0128] Furthermore, it can be provided that the first workpiece table 19 has at least one first recess 55 through which a machining tool 51 can be passed.

[0129] The second workpiece table 20 can, mutatis mutandis, have the above-described form of the off-center arrangement of the workpiece holders or the provision of a recess, although for the sake of simplicity, a detailed description is omitted.

[0130] Of course, the characteristics described above can also be applied to the execution according to Fig. 2 apply.

[0131] In the Fig. 4 and Fig. 5 shows a schematic representation of further and possibly independent embodiments of the machine tool 1, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 1 to 3. To avoid unnecessary repetition, please refer to the detailed description in the previous Fig. 1 to 3. In particular, it is pointed out that the embodiment of those machine tools 1 which are shown in the Fig. 4 and Fig. 5, the same features or at least partially the same features as that embodiment of the machine tool 1 which is shown in Fig. 1. For a better understanding, the Fig. 5 a highly schematically simplified representation has been chosen.

[0132] Fig. 4 shows a schematic representation of the machine tool 1 for machining workpieces 25, 31, 28, 34.

[0133] In contrast to the execution according to Fig. 1 can be executed according to Fig. 4, a single swivel table 59 may be provided. The swivel table 59 may have the first front workpiece holder 24 on a swivel table front side 60 for directly and immovably receiving the first workpiece 25 on the swivel table 59. The swivel table 59 may also have a second front workpiece holder 30 on the swivel table front side 60 for directly and immovably receiving the second workpiece 31 on the swivel table 59.

[0134] Furthermore, the swivel table 59 can have a first rear workpiece holder 27 on a swivel table rear side 61 for directly and immovably receiving a first rear workpiece 28 on the swivel table 59. Furthermore, the swivel table 59 can have a second rear workpiece holder 33 on the swivel table rear side 61 for directly and immovably receiving a second rear workpiece 34 on the swivel table 59.

[0135] Furthermore, it can be provided that the swivel table 59 is pivotably mounted about a swivel table axis 62, which is aligned parallel to the horizontal X-axis (10). Depending on the pivot position of the swivel table 59, the first front workpiece holder 24 and the second front workpiece holder 30 can be pivoted into the machining space 44, or the first rear workpiece holder 27 and the second rear workpiece holder 33 can be pivoted into the machining space 44.

[0136] Such a design has the advantage that the forces which are introduced by the first spindle axis 7 onto the swivel table 59 and which are introduced by the second spindle axis 8 onto the swivel table 59 are balanced out by the opposing positioning with respect to the swivel table axis 62, so that the torque of the swivel table 59 about the swivel table axis 62 or the required torque of the drive motor for holding the swivel table 59 in position during machining can be kept as low as possible.

[0137] As from Fig. As can be further seen from Figure 4, the machine tool 1 may include a tool magazine 63. The tool magazine 63 may include a first tool turret 64 and a second tool turret 65.

[0138] In particular, it can be provided that the first tool turret 64, which is designed to accommodate a plurality of machining tools 51, is arranged laterally to the workpiece clamping device 18. The first work spindle 5 can be displaceable relative to the first tool turret 64, so that the machining tools 51 can be received directly from the first tool turret 64 into the first work spindle 5. The first tool turret 64 can be rotatably mounted about a first turret axis 66. In particular, it can be provided that the first tool turret 64 has a plurality of first tool receiving locations 68 in a circular pattern.

[0139] Furthermore, it can be provided that a second tool turret 65 is arranged laterally to the workpiece clamping device 18, which is designed to accommodate a plurality of machining tools 51. The second work spindle 6 can be displaceable relative to the second tool turret 65, so that the machining tools 51 can be received directly from the second tool turret 65 into the second work spindle 6. The second tool turret 65 can be rotatably mounted about a second turret axis 67. In particular, it can be provided that the second tool turret 65 has a plurality of second tool receiving locations 69 in a circular pattern.

[0140] Of course, it is also conceivable that the first tool turret 64 and the second tool turret 65 are arranged in a mirrored design on the second side of the workpiece clamping device 18.

[0141] The described tool magazine 63 can of course also be used in all other design variants of the machine tool 1.

[0142] As from Fig. 5, it can be provided that the first front workpiece holder 24 is arranged at a first front workpiece holder distance 56 from the swivel table axis 62 and that the second rear workpiece holder 33 is arranged at a second rear workpiece holder distance 58 from the swivel table axis 62. The first front workpiece holder distance 56 and the second rear workpiece holder distance 58 can be of different sizes. The swivel table 59 can have recesses 70 through which a machining tool 51 can be passed in order to machine the rear side of the workpiece.

[0143] The angular position of the swivel table 59, as shown in Fig. 5 can be described as a vertical position, with an angle 71 of pivoting being 0°.

[0144] In the embodiment according to Fig. 6, the first front workpiece holder 24 and the second rear workpiece holder 33 are arranged directly opposite each other on the swivel table 59.

[0145] As from Fig. 6, it can be provided that in one work step the swivel table 59 is tilted about the swivel table axis 62 at an angle 71 of 90° to a vertical position, wherein at the same time the first workpiece 25 is machined by means of the second work spindle 6 and the second rear workpiece 34 is machined by means of the first work spindle 5.

[0146] In the Fig. 7 shows a schematic representation of a further and possibly independent embodiment of the machine tool 1, wherein the same reference numerals or component designations are used for the same parts as in the previous Fig. 1 to 6. To avoid unnecessary repetition, please refer to the detailed description in the previous Fig. 1 to 6. In particular, it is pointed out that the spindle adjustment device 3 of the version of the machine tool 1 which is shown in Fig. 7, can also be applied to the remaining embodiments described. In the Fig. 7 shows the machine tool 1 in a perspective view from behind.

[0147] As from Fig. 7, it can be provided that a first main adjustment unit 12a and a second main adjustment unit 12b are formed, which can each be displaced independently of one another in the direction of the X-axis 10 relative to the machine frame 2.

[0148] Furthermore, it can be provided that the first work spindle 5 is arranged on a first height adjustment unit 14a and the second work spindle 6 is arranged on a second height adjustment unit 14 and can thus be displaced independently of one another along a Y-axis 11. In this embodiment, the first height adjustment unit 14 can have a first drive and the second height adjustment unit 14 can have a second drive. The first height adjustment unit 14a can be mounted on the first main adjustment unit 12a by means of a first Y-axis linear guide 15a. The second height adjustment unit 14a can be mounted on the second main adjustment unit 12a by means of a second Y-axis linear guide 15a.

[0149] In such an embodiment variant, it can be provided that the work spindles 5, 6 are individually and independently adjustable in the Z-axis 9, in the X-axis 10 and in the Y-axis 11 relative to the machine frame 2 and thus have an individual drive for each of the adjustment directions.

[0150] The structure as it is in Fig. 7, enables the first work spindle 5 to be moved to the second front workpiece holder 30 in order to machine the second workpiece 31 and the second work spindle 6 to be moved to the first front workpiece holder 24 in order to machine the first workpiece 25.

[0151] In particular, it can be provided that the first height adjustment unit 14a and the second height adjustment unit 14 can be guided close to one another to such an extent that the first work spindle 5 can be guided exactly above the second work spindle 6. In this case, the first height adjustment unit 14a can be supported on the second height adjustment unit 14 in order to achieve increased stability.

[0152] In the Fig. Figure 8 shows a schematic embodiment of a possible design of the first work spindle 5 in a plan view. This design can be applied to all other embodiments of the machine tool 1.

[0153] As from Fig. 8, it can be provided that a first swivel head 72 is formed, by means of which the first work spindle 5 can be swiveled about the vertical Y-axis 11.

[0154] In the Fig. Figure 9 shows a schematic embodiment of a possible design of the second work spindle 6 in a plan view. This design can be applied to all other embodiments of the machine tool 1.

[0155] As from Fig. 9, it can be provided that a second swivel head 73 is formed, by means of which the second work spindle 6 can be swiveled about the vertical Y-axis 11.

[0156] As from Fig.10, the described method for operating the machine tool 1 can also be applied to a machine tool 1 with a single first work spindle 5. In particular, the method step of alternately machining the first workpiece 25 and the first rear workpiece 28 using the same machining tool 51 clamped in the first work spindle 5, wherein the first front workpiece holder 24 of the workpiece clamping device 18 or the first rear workpiece holder 27 of the workpiece clamping device 18 is pivoted into the machining space 44 of the machine tool 1 in a pendulum operation, can be advantageous on such a machine tool 1, since the non-productive times can be shortened by requiring less frequent tool changes.

[0157] The embodiments show possible embodiments, whereby it should be noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but rather various combinations of the individual embodiments with each other are also possible and this possibility of variation lies within the skill of the person skilled in the art in this technical field due to the teaching of technical action by means of the objective invention.

[0158] The scope of protection is determined by the claims. However, the description and drawings must be used to interpret the claims. Individual features or combinations of features from the various embodiments shown and described may represent independent inventive solutions. The problem underlying these independent inventive solutions can be derived from the description.

[0159] All information on value ranges in this description is to be understood as including any and all sub-ranges thereof, e.g. the information 1 to 10 is to be understood as including all sub-ranges starting from the lower limit of 1 and the upper limit of 10, ie all sub-ranges begin with a lower limit of 1 or greater and end with an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

[0160] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size. Reference symbol list 1 machine tool 2 machine frame 3 common spindle adjustment device 4 Working head 5 first work spindle 6 second work spindle 7 first spindle axis 8 second spindle axis 9 Z-axis 10 X-axis 11 Y-axis 12 Main adjustment unit 13 X-axis linear guide 14 Height adjustment unit 15 Y-axis linear guide 16 first Z-axis linear guide 17 second Z-axis linear guide 18 Workpiece clamping device 19 first workpiece table 20 second workpiece table 21 first swivel axis 22 second swivel axis 23 first workpiece table front 24 first front workpiece holder 25 first workpiece 26 first workpiece table back 27 first rear workpiece holder 28 first rear workpiece 29 second workpiece table front 30 second front workpiece holder 31 second workpiece 32 second workpiece table back 33 second rear workpiece holder 34 second rear workpiece 35 first swivel bearing first workpiece table 36 second swivel bearing first workpiece table 37 first swivel bearing second workpiece table 38 second swivel bearing second workpiece table 39 Distance between workpiece tables 40 first drive unit 41 second drive unit 42 Distance between first work spindle and second work spindle 43 digital computers 44 processing room 45 Loading space 46 first radius 47 second radius 48 first flight circle 49 second flight circle 50 flight circle distance 51 Editing tool 52 Partition segment 53 first concave shape 54 second concave shape 55 first recess 56 first front workpiece holder distance 57 first rear workpiece holder distance 58 second rear workpiece holder distance 59 Swivel table 60 Swivel table front 61 Swivel table rear 62 swivel table axis 63 tool magazine 64 first tool turret 65 second tool turret 66 first turret axis 67 second turret axis 68 first tool holder 69 second tool holder 70 recess 71 angles 72 first swivel head 73 second swivel head 74 first sealing element 75 second sealing element QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 3659744A1 [0002, 0003]

Claims

[1] Machine tool (1) comprising: a machine frame (2) in which a loading space (45) and a processing space (44) are formed; a first work spindle (5) which is rotatably mounted about a first spindle axis (7), wherein the first work spindle (5) is slidably mounted on the machine frame (2) along a horizontal Z-axis (9), along a horizontal X-axis (10) and along a vertical Y-axis (11); a workpiece clamping device (18) which is designed to hold at least a first workpiece (25) and a second workpiece (31), wherein a second work spindle (6) is formed, which is rotatably mounted about a second spindle axis (8), wherein the second work spindle (6) is slidably mounted on the machine frame (2) along the Z-axis (9), along the X-axis (10) and along the Y-axis (11), wherein the first work spindle (5) and the second work spindle (6) are arranged vertically one above the other and the first work spindle (5) is designed to machine the first workpiece (25) and the second work spindle (6) is designed to machine the second workpiece (31), characterized by , that a first tool turret (64) is arranged laterally to the workpiece clamping device (18), which is designed to accommodate a plurality of machining tools (51), wherein the first work spindle (5) is displaceable relative to the first tool turret (64) so ​​that the machining tools (51) can be accommodated directly from the first tool turret (64) into the first work spindle (5), and that a second tool turret (65) is arranged laterally to the workpiece clamping device (18), which is designed to receive a plurality of machining tools (51), wherein the second work spindle (6) is displaceable towards the second tool turret (65) so that the machining tools (51) can be received directly from the second tool turret (65) into the second work spindle (6). [2] Machine tool (1) according to claim 1, characterized bythat a swivel table (59) is formed, wherein the swivel table (59) has a first front workpiece holder (24) for the direct and immovable reception of the first workpiece (25) on the swivel table (59) and a second front workpiece holder (30) for the direct and immovable reception of the second workpiece (31) on the swivel table (59) and a first rear workpiece holder (27) for directly and immovably receiving a first rear workpiece (28) on the swivel table (59) and a second rear workpiece holder (33) for directly and immovably receiving a second rear workpiece (34) on the swivel table (59), wherein the swivel table (59) is pivotally mounted about a swivel table axis (62) which is aligned parallel to a horizontal X-axis (10), Depending on the swivel position of the swivel table (59) the first front workpiece holder (24) and the second front workpiece holder (30) can be pivoted into the machining space (44) or the first rear workpiece holder (27) and the second rear workpiece holder (33) can be pivoted into the machining space (44). [3] Machine tool (1) according to claim 2, characterized by in that the first front workpiece holder (24) is arranged at a first front workpiece holder distance (56) from the swivel table axis (62) and in that the second rear workpiece holder (33) is arranged at a second rear workpiece holder distance (58) from the swivel table axis (62), wherein the first front workpiece holder distance (56) and the second rear workpiece holder distance (58) are of different sizes and wherein the swivel table (59) has recesses (70) through which a machining tool (51) can be guided. [4] Machine tool (1) according to claim 1, characterized bythat the workpiece clamping device (18) comprises a first workpiece table (19) and a second workpiece table (20), wherein the first workpiece table (19) is pivotally mounted about a first pivot axis (21) which is aligned parallel to the X-axis (10), and the second workpiece table (20) is pivotally mounted about a second pivot axis (22) which is aligned parallel to the X-axis (10), and that the first work spindle (5) is assigned to the first workpiece table (19) and the second work spindle (6) is assigned to the second workpiece table (20), wherein the first workpiece table (19) has a first front workpiece holder (24) and a first rear workpiece holder (27) and the second workpiece table (20) has a second front workpiece holder (30) and a second rear workpiece holder (33), wherein depending on the pivot position of the first workpiece table (19) and the second workpiece table (20),the first front workpiece holder (24) and the second front workpiece holder (30) can be pivoted into the machining space (44) or the first rear workpiece holder (27) and the second rear workpiece holder (33) can be pivoted into the machining space (44). [5] Machine tool (1) according to claim 4, characterized byin that the first front workpiece holder (24) is arranged at a first front workpiece holder distance (56) from the first pivot axis (21) and in that the first rear workpiece holder (27) is arranged at a first rear workpiece holder distance (57) from the first pivot axis (21), wherein the first front workpiece holder distance (56) and the first rear workpiece holder distance (57) extend into different sides of the first workpiece table (19) with respect to the first pivot axis (21), and wherein the first workpiece table (19) has at least one first recess (55) through which a machining tool (51) can be guided. [6] Machine tool (1) according to claim 4 or 5, characterized byin that the first workpiece table (19) has a first radius (46) which is adapted to a first flight circle (48) of the first workpiece table (19) and the second workpiece table (20) has a second radius (47) which is adapted to a second flight circle (49) of the second workpiece table (20), wherein the first flight circle (48) of the first workpiece table (19) and the second flight circle (49) of the second workpiece table (20) are arranged at a flight circle distance (50) between 0.1 mm and 10 mm, in particular between 0.2 mm and 5 mm, preferably between 0.5 mm and 2 mm from one another. [7] Machine tool (1) according to one of claims 4 to 6, characterized by that the first workpiece table (19), in particular at the first radius (46), has a first sealing element (74) and the second workpiece table (20), in particular at the second radius (47), has a second sealing element (75). [8] Machine tool (1) according to claim 4 or 5 or 7, characterized byin that the first workpiece table (19) has a first flight circle (48) of the first workpiece table (19) and the second workpiece table (20) has a second flight circle (49) of the second workpiece table (20), wherein the first flight circle (48) of the first workpiece table (19) and the second flight circle (49) of the second workpiece table (20) are arranged at a flight circle distance (50) from one another, wherein a partition wall segment (52) is arranged between the first workpiece table (19) and the second workpiece table (20), wherein the partition wall segment (52) has a shape adapted to the first flight circle (48) and the second flight circle (49). [9] Machine tool (1) according to one of the preceding claims, characterized by that the first work spindle (5) and the second work spindle (6) can be moved independently of one another in the horizontal Z-axis (9) and in the vertical Y-axis (11). [10] Machine tool (1) according to one of the preceding claims, characterized by that a first pivoting head (72) is formed, by means of which the first work spindle (5) can be pivoted about the vertical Y-axis (11) and that a second pivoting head (73) is formed, by means of which the second work spindle (6) can be pivoted about the vertical Y-axis (11). [11] Machine tool (1) according to one of the preceding claims, characterized by that on a second side of the workpiece clamping device (18) or at a second longitudinal end of the workpiece clamping device (18) there are also two tool turrets arranged, which have a similar structure to the first tool turret (64) and second tool turret (65) already described. [12] Machine tool (1) according to one of the preceding claims, characterized bythat the first tool turret (64) is rotatably mounted about a first turret axis (66) and that the first tool turret (64) has a plurality of first tool receiving locations (68) in a circular pattern and that the second tool turret (65) is rotatably mounted about a second turret axis (67) and that the second tool turret (65) has a plurality of second tool receiving locations (69) in a circular pattern.

Images