Method and device for machining disc-shaped workpieces

Abstract

Method for machining disc-shaped workpieces (2), comprising providing a machine tool (1) comprising a machine frame (3), an x-slide (8) arranged on the machine frame (3) so as to be movable in an x-direction, a z-slide (12) arranged on the x-slide (8) so as to be movable in a z-direction, a workpiece clamping device (17) arranged on the z-slide (12) and rotatable about a rotary axis extending in the z-direction, a stationary first tool clamping device (5) arranged on the machine frame (3) comprising at least a first tool holder (20) with a first tool (21) and a second tool (22) for machining a first flat surface (18) and a second flat surface (19) of the workpiece (2), and a stationary second tool clamping device (6) arranged on the machine frame (3).comprising a second tool holder (24) with a third tool (28) for machining the first planar surface (18) of the workpiece (2) and a third tool holder (25) with a fourth tool (30) for machining the second planar surface (19) of the workpiece (2), wherein the second tool holder (24) and the third tool holder (25) are displaceable relative to each other, clamping the workpiece (2) in the workpiece clamping device (17), machining the two planar surfaces (18, 19) of the workpiece (2) in a first machining step by the first and second tools (21, 22), wherein the two planar surfaces (18, 19) are machined by the first and second workpiece (21,22) are machined simultaneously, or first the first planar surface (18) is machined by the first tool (21) and then the second planar surface (19) is machined by the second tool (22), or first the second planar surface (19) is machined by the second tool (22) and then the first planar surface (18) is machined by the first tool (21), the optional machining of the two planar surfaces (18, 19) of the workpiece (2) in a second machining step by the third and fourth tools (28, 30), wherein the two planar surfaces (18, 19) are machined simultaneously by the third and fourth workpieces (28, 30), and the unclamping of the finished workpiece (2).

Description

[0001] The invention relates to a method for machining disc-shaped workpieces. Furthermore, the invention relates to a machine tool, in particular for machining disc-shaped workpieces.

[0002] Machine tools for machining disc-shaped workpieces are known from the prior art, for example CN 214 054 355 U.

[0003] Prior art machine tools have the disadvantage that their workpiece clamping devices and / or tool clamping devices have many degrees of freedom, which increases the risk of individual drives failing. Furthermore, the large number of degrees of freedom and the necessary workpiece re-clamping in prior art machines result in lower accuracy. Additionally, workpiece re-clamping requires extra time at the machine, thus increasing machine uptime.

[0004] The invention is based on the objective of improving a method for machining disc-shaped workpieces.

[0005] This problem is solved by a method with the features of claim 1. According to the invention, it was found that a method in which the disc-shaped workpiece does not need to be reclamped and yet can be machined on both planar surfaces reduces machine uptime and increases the achievable manufacturing accuracy. This allows, for example, more disc-shaped workpieces to be machined in the same amount of time. A higher throughput is therefore achieved.

[0006] Disc-shaped workpieces are defined as geometric elements that have a circular shape, at least approximately, in at least one cross-section. Furthermore, the dimension perpendicular to the circular cross-section is significantly smaller than the diameter of the circular cross-section. These disc-shaped workpieces are preferably brake discs for the automotive industry.

[0007] Clamping the workpiece into the workpiece clamping device can preferably be automated. Alternatively, the workpiece can be clamped into the workpiece clamping device manually.

[0008] To enable machining of both flat surfaces without reclamping, the workpiece is clamped in the workpiece clamping device in such a way that both flat surfaces are freely accessible. For this purpose, the disc-shaped workpiece preferably has a bore at its center. The workpiece is then clamped from the inside within this bore, preferably by clamping jaws that can be moved outwards or by a clamping mandrel. Additionally, the workpiece can have grooves in the bore into which clamping jaws can engage. This secures the workpiece against rotation.

[0009] The workpiece clamping device can be designed to be moved pneumatically, hydraulically, or electromechanically. The workpiece clamping device can also be designed to be moved by pushing a button.

[0010] The different machining options available for the two flat surfaces of the workpiece in a first machining step, using the first and second tools, allow the process to flexibly machine disc-shaped workpieces of varying thicknesses. For example, the distance between the first and second tools can be adjusted so that they can machine a disc-shaped workpiece simultaneously. Workpieces with a thickness less than the dimension of the machining gap between the first and second tools can be machined first on one of the two flat surfaces and then on the other. The system thus allows for the most efficient machining of fixed thicknesses on disc-shaped workpieces by simultaneously machining both flat surfaces, and for the flexible machining of thinner disc-shaped workpieces by sequentially machining the flat surfaces.

[0011] The first processing step can be carried out with the addition of a temperature control medium. Alternatively, the first processing step can be carried out without a temperature control medium.

[0012] The second machining step is optional. This step can improve the surface accuracy of the disc-shaped workpiece. Such an improvement is advantageous, for example, when machining brake discs, as it ensures they are as smooth as possible, thus enabling the highest possible braking force after manufacturing. However, this type of finishing can also be performed on a separate machine or may not be necessary for some disc-shaped workpieces. In such cases, the second machining step can be omitted entirely, further reducing machine time for a single workpiece and increasing the throughput of the machine tool.

[0013] The workpiece is preferably removed from the clamping mechanism automatically. In this process, the workpiece is safely and undamaged placed in a predefined position. Alternatively, the workpiece can be removed manually.

[0014] A method according to claim 2 offers greater variability in manufacturing. By repositioning the third and fourth tools relative to each other in the Z-direction, a specific machining dimension can be set for any workpiece thickness. This enables finishing in the second optional machining step for any workpiece thickness. A large number of different workpiece thicknesses can thus be manufactured efficiently on the machine tool.

[0015] A displacement of the tools relative to each other preferably means that at least one of the tools can be moved linearly by a drive. The movement of the at least one tool can be achieved, for example, by an electric motor along tool rails. Any suitable drive capable of generating a linear motion is conceivable.

[0016] A method according to claim 3 increases the variability of the manufacturing process. The possibility of different temperature control options allows for the processing of various materials and / or the implementation of different machining methods. Furthermore, the machining process can be optimized by means of the temperature control medium, depending on the workpiece dimensions to be removed.

[0017] A typical temperature control medium is a tempered oil-water mixture, which is also commonly known as "coolant" or "lubricant".

[0018] A method according to claim 4 is particularly efficient. By performing a turning operation in the first machining step, a large amount of material can be efficiently and quickly removed from the workpiece in order to machine it to a desired dimension.

[0019] A method according to claim 5 makes it possible to produce the smoothest possible surface on the planar surfaces. This is particularly advantageous in the manufacture of disc brakes, as it ensures that they produce a proper braking effect immediately after manufacturing and do not need to be worn down by the brake pads first. Turning and milling or grinding are suitable processes for this purpose, as they remove only a small amount of material and ensure a smooth surface. This allows, in particular, the elimination of irregularities resulting from the turning process of the first machining step.

[0020] The invention is further based on the objective of improving a machine tool, in particular for machining disc-shaped workpieces, especially according to the method according to the invention.

[0021] This problem is solved by the machine tool with the features according to claim 6. The machine tool according to the invention achieves a compact design with a simultaneously uncomplicated construction and as few axes of movement as possible. This ensures high accuracy during machining. In addition, a machine tool according to the invention has components that can fail.

[0022] According to the invention, it has been recognized that machine tools with two tool clamping devices, each with two tools, capable of machining two different flat surfaces of a workpiece, particularly a disc-shaped workpiece, without reclamping the workpiece, enable particularly time-efficient and precise manufacturing. Since reclamping the workpiece is unnecessary, tolerance errors, which can occur especially during reclamping, do not accumulate. This ensures high accuracy. Furthermore, a reclamping process takes time, which can be saved on the machine tool according to the invention. In addition, the stationary tool clamping devices ensure high stability during workpiece machining and thus precise and reproducible manufacturing tolerances.

[0023] The machine frame forms the basic structure of the machine tool. All components of the machine tool are arranged on the machine frame.

[0024] The X- and Z-slides allow the workpiece clamping device to be moved in the X and Z directions. This mobility in the X and Z directions enables the workpiece clamping device to reach all relevant positions.

[0025] Preferably, the x-carriage is mounted on the machine frame and the z-carriage on the x-carriage. Alternatively, the z-carriage can be mounted on the machine frame and the x-carriage on the z-carriage. In this case, the workpiece clamping device would be mounted on the x-carriage and not on the z-carriage.

[0026] The workpiece clamping device is rotatable about a rotary axis extending in the Z-direction. For this purpose, the workpiece clamping device can have a rotary spindle. This rotatable capability allows a clamped workpiece to be rotated. This enables the use of stationary, non-rotatable machining tools for machining the workpiece. Preferably, rotation about a rotary axis extending in the Z-direction constitutes the only rotational degree of freedom of the workpiece clamping device. Alternatively, the workpiece clamping device can have more than one rotational degree of freedom. The workpiece clamping device can have more than one rotational degree of freedom, in particular, if more complex machining operations on the workpiece are required.

[0027] The workpiece clamping device can preferably be designed in such a way that it can grip a disc-shaped workpiece in a bore in such a way that both flat surfaces of the workpiece are free and can be machined.

[0028] The first tool clamping device has at least one tool holder for a first and a second tool. Tools here are understood to be, in particular, machining blades. For example, the at least one tool holder can be designed as a two-edged tool, which has two oppositely arranged cutting blades that form the tools. Alternatively, individual tools can be arranged in at least two first tool holders. The distance between the first and second tools can be adjustable, in particular manually or automatically. The distance can be adjustable, in particular via a drive or via manual adjustment.

[0029] A workpiece can be machined by the first and second tools either simultaneously on both planar surfaces or alternately on the planar surfaces. Simultaneous machining is particularly possible when the target thickness of the workpiece corresponds to the height of a machining gap between the first and second tools.

[0030] The third and fourth tool holders of the second tool clamping device are movable relative to each other. Specifically, they can be moved relative to each other by a suitable drive. This allows the machining gap between the third and fourth tools to be adjusted to the thickness of the workpiece. This adjustment enables simultaneous machining of both flat surfaces of workpieces of any thickness.

[0031] The third and fourth tools can preferably be driven by drives, in particular rotary drive motors. By enabling the third and fourth tools to be driven by rotary drive, advantageous machining processes such as grinding or mill-turning can be carried out, whereby the tools wear evenly over their circumference and not just at specific points or in certain areas.

[0032] Preferably, a temperature control medium supply can be arranged on the first tool clamping device and / or the second tool clamping device, through which temperature control media can be supplied. Various temperature control media, such as tempered air, a tempered air-oil mixture, and / or a tempered water-oil mixture, can be supplied via the temperature control medium supply. This allows machining operations to be carried out in "wet" or "dry" mode.

[0033] A machine tool according to claim 7 exhibits higher stability and thus enables more precise manufacturing. In particular, the workpiece clamping device has no translational degree of freedom in the Y-direction, i.e., it cannot be displaced in the Y-direction.

[0034] A machine tool according to claim 8 enables high variability in manufacturing and autonomous operation. A tool-changing function allows the first and second tools to be automatically changed when worn. Furthermore, the tool-changing function can incorporate various first tool holders with different machining gap dimensions. This allows workpieces of different thicknesses to be machined simultaneously on both faces of the first tool clamping device.

[0035] Preferably, the tool changing function is implemented as a rotary tool changer or tool turret. In a tool turret or rotary tool changer design, the first tool clamping device preferably has exactly one rotational degree of freedom. This single rotational degree of freedom is preferably achieved by rotation about the X-axis.

[0036] A machine tool according to claim 9 enables automated or autonomous operation. The machine tool can have separate feeding and discharge devices. Alternatively, the machine tool can have a combined feeding and discharge device. A combined feeding and discharge device allows for a particularly space-saving design of the machine tool.

[0037] A machine tool according to claim 10 enables particularly flexible manufacturing. Either the third and fourth tools can be driven by rotary motion, and / or the workpiece. This allows, among other things, superimposed movements when both the tool and the third and fourth tools are driven by rotary motion.

[0038] A machine tool according to claim 11 represents a ready-to-use machine tool.

[0039] A machine tool according to claim 12 enables the machining of the workpiece's planar surfaces simultaneously and / or sequentially using opposing tools, without rotating the workpiece. This therefore allows for a simple and stable machine tool design with the fewest possible degrees of freedom required.

[0040] A machine tool according to claim 13 represents a preferred embodiment. By designing the first and second tools as turning tools, a rough machining of the workpiece can be carried out in a first machining step, in which a relatively large amount of material can be applied.

[0041] A machine tool according to claim 14 represents a preferred embodiment of the machine tool. By designing the third and fourth tools as milling and / or grinding wheels, it is possible to finish the workpiece and produce a desired surface finish. Such a surface finish is particularly necessary in the production of disc-shaped workpieces, especially brake discs, so that the brake discs can generate the desired braking force after manufacturing.

[0042] An embodiment of the invention is explained in more detail below. The figures shown are: Fig. 1 an embodiment of a machine tool according to the invention, Fig. 2 a schematic representation of the inventive method for processing hard-coated discs.

[0043] The Fig. Figure 1 shows a machine tool 1 for machining disc-shaped workpieces 2. The machine tool 1 has a machine frame 3. Attached to the machine frame 3 are a workpiece slide 4, a first tool clamping device 5, a second tool clamping device 6, and a feeding and unloading device 7 for feeding and unloading disc-shaped workpieces 2.

[0044] The disc-shaped workpieces 2 have a first planar surface 18 and a second planar surface 19.

[0045] The workpiece slide 4 comprises an x-slide 8, which can be moved along a rail 9 by means of a motor 10 via a threaded spindle 11 in the X direction. A z-slide 12 is arranged on the x-slide 8, which can be moved along the rails 13 by means of a motor 14 via a threaded spindle 15 in the Z direction.

[0046] A rotary spindle 16 is arranged on the z-slide 12. A workpiece clamping device 17, also arranged on the rotary spindle 16, can be driven to rotate about the z-axis by means of the rotary spindle 16. The workpiece clamping device 17 can be used to clamp the disc-shaped workpieces 2. For this purpose, the workpiece clamping device 17 preferably has a clamping mechanism that can engage in a bore of a disc-shaped workpiece 2 and thus hold the disc-shaped workpiece 2 securely against rotation. Alternatively, the workpiece clamping device 17 can have a clamping mechanism that grips and holds the disc-shaped workpieces 2 at one of their flat surfaces 18, 19.

[0047] The first tool clamping device 5 is fixedly mounted on the machine frame 3. Therefore, the first tool clamping device 5 has no lateral degrees of freedom. The first tool clamping device 5 has a tool-changing function, which is implemented as a tool turret. Due to its design as a tool turret, the first tool clamping device 5 can be rotated about the X-axis. The first tool clamping device 5 is rotationally fixed about the Y- and Z-axes. Therefore, the first tool clamping device 5 has exactly one rotational degree of freedom. At least one first tool holder 20 is arranged at each position of the tool turret of the first tool clamping device 5.

[0048] In the Fig. Figure 1 primarily shows a first tool holder 20, which includes a first tool 21 and a second tool 22. The first tool 21 and the second tool 22 are oriented in opposite directions, enabling the machining of the first flat surface 18 and the second flat surface 19 of the disc-shaped workpieces 2. A first machining gap 23 is formed between the first tool 21 and the second tool 22. The first tool holder 20, the first tool 21, and the second tool 22 thus form a double-edged tool. Optionally, the distance between the first tool 21 and the second tool 22 can be adjusted. Adjustment of the distance can be done manually or automatically via a drive mechanism.

[0049] As an alternative to the illustrated double-edged tool configuration, the first tool 21 and the second tool 22 can be arranged in separate first tool holders 20. For example, one first tool holder 20 can be fixed in position on the machine frame, and only a second first tool holder 20 can be attached to the first tool clamping device 5. Alternatively, the first tool clamping device 5 can have two tool change rings, which are particularly rotatable independently of each other, and on each of which first tool holders 20 with a first tool 21 and second tools 22 are arranged.

[0050] The second tool clamping device 6 is fixedly mounted on the machine frame 3. The second tool clamping device 6 comprises a second tool holder 24 and a third tool holder 25. The second tool holder 24 and the third tool holder 25 are mounted on rails 26 on the second tool clamping device 6 and are movable relative to each other in the Z-direction. The second tool holder 24 includes a third tool 28 mounted on a rotary spindle 27. The third tool holder 25 includes a fourth tool 30 mounted on a rotary spindle 29.

[0051] The third tool 28 and the fourth tool 30 are designed as turning and milling discs and / or grinding discs. An adjustable second machining gap 31 is formed between the third tool 28 and the fourth tool 30. The second machining gap 31 is adjusted relative to each other by a drive mechanism (not shown) that moves the second tool holder 24 and the third tool holder 25.

[0052] Fig. Figure 2 schematically shows the procedure for machining the disc-shaped workpieces 2. For this purpose, in a first step S1, a Fig. 1 The machine tool 1 shown according to the invention is provided.

[0053] In a second step S2, a disc-shaped workpiece 2 is clamped into the workpiece clamping device 17. For this purpose, the workpiece clamping device 17 is moved via the tool slide 4, in particular via the x-slide 8 and the z-slide 12, to a position above the infeed and outfeed device 7. Subsequently, the workpiece clamping device 17 is moved via the z-slide 12 in the direction of the disc-shaped workpiece 2. The disc-shaped workpiece 2 is then secured in the workpiece clamping device 17 by a suitable clamping mechanism, as described above. In a third step S3, the first flat surface 18 and the second flat surface 19 of the disc-shaped workpiece 2 are machined by the first tool 21 and the second tool 22. For this purpose, the disc-shaped workpiece 2 is positioned in the first machining gap 23 and rotated by the spindle 16.Provided that the dimension of the first machining gap 23 is matched to the desired thickness of the disc-shaped workpiece 2, the first planar surface 18 and the second planar surface 19 are machined simultaneously by the first tool 21 and the second tool 22. For this purpose, the disc-shaped workpiece 2 is first moved to the correct Z-height and then only moved in the X-direction by the x-slide 8.

[0054] If the dimensions of the first machining gap 23 are larger than the desired thickness of the disc-shaped workpiece 2, the first planar surface 18 can be machined first by the first tool 21 and then the second planar surface 19 by the second tool 22. Alternatively, the second planar surface 19 can be machined first by the second tool 22 and then the first planar surface 18 by the first tool 21. For this purpose, the disc-shaped workpiece 2 is moved to the required Z-height by the z-slide 12 and then a machining feed is generated by the x-slide in the X-direction.

[0055] In a further optional fourth step S4, the disc-shaped workpiece 2 can be finished by the third tool 28 and the fourth tool 30. This step S4 is only necessary if a certain surface finish or accuracy is required for the finished disc-shaped workpiece 2.

[0056] In the fourth step S4, the height of the second machining gap 31 is first set to a desired final dimension by moving the second tool holder 24 and the third tool holder 25 relative to each other in the Z direction. Subsequently, the disc-shaped workpiece 2 is moved to a Z height by the z-slide 12 and then by the x-slide 8 into the second machining gap 31.

[0057] During machining by the third tool 28 and the fourth tool 30, preferably the third tool 28 and the fourth tool 30 are driven by rotation, but not the disc-shaped workpiece 2. Alternatively, the third tool 28, the fourth tool 30 and the disc-shaped workpiece 2 can be driven by rotation. Alternatively, only the disc-shaped workpiece 2 can be driven by rotation.

[0058] Machining with the third tool 28 and the fourth tool 30 can be carried out under various temperature control conditions. Machining can be performed without the use of a temperature control medium. Machining can be performed using temperature-controlled air. Machining can be performed using temperature-controlled air and an added alcohol. Machining can be performed using a temperature-controlled oil-water mixture. A suitable temperature control medium can be supplied via a [missing information - likely a specific component or component]. Fig. 1. A supply line not shown will be used.

[0059] In a fifth step S5, the finished workpiece 2 is unclamped. For this purpose, the workpiece 2 is placed onto the infeed and outfeed device 7 using the workpiece slide 4. The unloading process is the reverse of the picking process. QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] CN 214 054 355 U

[0002]

Claims

[1] Method for machining disc-shaped workpieces (2) comprising the steps: - Provision of a machine tool (1) comprising -- a machine frame (3), -- an x-slide (8) arranged on the machine frame (3) so as to be movable in an x-direction, -- a z-slide (12) arranged on the x-slide so as to be movable in a z-direction, -- a workpiece clamping device (17), --- which is arranged on the z-carriage (12) and --- which can be driven to rotate about an axis of rotation extending in the z-direction, -- comprising a stationary first tool clamping device (5) arranged on the machine frame (3) --- at least one first tool holder (20) with a first tool (21) and a second tool (22) for machining a first planar surface (18) and a second planar surface (19) of the workpiece (2) and -- a stationary second tool clamping device (6) arranged on the machine frame (3), comprising --- a second tool holder (24) with a third tool (28) for machining the first planar surface (18) of the workpiece (2) and --- a third tool holder (25) with a fourth tool (30) for machining the second planar surface (19) of the workpiece (3), wherein --- the second tool holder (24) and the third tool holder (25) are movable relative to each other, - Clamping the workpiece (3) into the workpiece clamping device (17), - Machining the two planar surfaces (18) of the workpiece (2) in a first machining step by the first and second tools (21, 22), wherein -- the two planar surfaces (18, 19) are machined simultaneously by the first and second workpieces (21, 22) or -- first the first planar surface (18) is machined by the first tool (21) and then the second planar surface (19) by the second tool (22) or -- first the second planar surface (19) is machined by the second tool (22) and then the first planar surface (18) by the first tool (21), - optional machining of the two planar surfaces (18, 19) of the workpiece (2) in a second machining step by the third and fourth tools (28, 30), wherein the two planar surfaces (18, 19) are machined simultaneously by the third and fourth workpiece (28, 30), - Unclamping the finished workpiece (2). [2] Method according to claim 1, characterized by, that before the second machining step a machining gap (31) between the third and fourth tools (28, 30) is set to a machining dimension of the workpiece (2) by moving the third and fourth tools (28, 30) relative to each other in the z-direction. [3] Method according to claim 1 or 2, characterized by , that the machining of the two planar surfaces (18, 19) by the third and fourth tools (28, 30) takes place under at least one of the following temperature control variants: - without the use of a temperature control medium, - using tempered air, - using tempered air and an added alcohol, or - using a tempered oil-water mixture. [4] Method according to any one of the preceding claims, characterized by that the first processing step is carried out as turning. [5] Method according to any one of the preceding claims, characterized by that the second machining step is carried out as turning and milling or as grinding. [6] Machine tool (1), in particular for machining disc-shaped workpieces (2), comprising - a machine frame (3), - an x-slide (8) arranged on the machine frame (3) so as to be movable in an x-direction, - a z-carriage (12) arranged on the x-carriage (8) so as to be movable in a z-direction, - a workpiece clamping device (17), -- which is arranged on the z-carriage (12) and -- which is rotatable about a rotary axis extending in the z-direction, - comprising a stationary first tool clamping device (5) arranged on the machine frame (3) -- at least one first tool holder (20) for a first tool (21) and a second tool (22) for machining a first planar surface (18) and a second planar surface (19) of the workpiece (2) and - a stationary second tool clamping device (6) arranged on the machine frame (3), comprising -- a second tool holder (24) for a third tool (28) for machining the first planar surface (18) of the workpiece (2) and -- a third tool holder (25) for a fourth tool (30) for machining the second planar surface (19) of the workpiece (2), wherein -- the second tool holder (24) and the third tool holder (25) are movable relative to each other. [7] Machine tool (1) according to claim 6, characterized by , that the workpiece clamping device (17) has only two translational degrees of freedom which extend in the x-direction and in the z-direction. [8] Machine tool (1) according to one of claims 6 to 7, characterized by , that the first tool clamping device (5) has a tool changing function. [9] Machine tool (1) according to any one of claims 6 to 8, characterized by a feed device (7) for feeding blanks (2) and / or a discharge device (7) for removing finished workpieces (2). [10] Machine tool (1) according to any one of claims 6 to 9, characterized by the second and / or the third tool holder (24, 25) is rotatable. [11] Machine tool (1) according to any one of claims 6 to 10, characterized by - a first tool (21) arranged in the at least one first tool holder (20), - a second tool (22) arranged in the at least one first tool holder (20), - a third tool (28) arranged in the second tool holder (24) and - a fourth tool (30) arranged in the third tool holder (25). [12] Machine tool (1) according to claim 11, characterized by , that - the cutting elements of the first and second tools (21, 22) are arranged in opposite directions and / or - the cutting elements or grinding elements of the third and fourth tools (28, 30) are arranged in opposite directions. [13] Machine tool (1) according to one of claims 11 or 12, characterized by , that the first and second tools (21, 22) are designed as turning tools. [14] Machine tool (1) according to any one of claims 11 to 13, characterized by , that the third and fourth tools (28, 30) are designed as turning milling discs and / or grinding discs.

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