Machine tools, especially lathes with auxiliary spindles

Abstract

A machine tool, such as a lathe, has a machine frame (110) having an upper tool carrier support portion (113), a lower tool carrier support portion (114), and a spindle carrier portion disposed between the upper and lower tool carrier support portions. The spindle carrier is disposed on or at the level of the spindle carrier portion of the machine frame (110) and supports a main spindle (121) configured to receive a workpiece, and a plurality of tool carriers, each supported on a tool carrier assembly (150) disposed on either the upper tool carrier support portion (113) or the lower tool carrier support portion (114) of the machine frame (110). The machine tool also includes an auxiliary spindle carrier (130) disposed on the spindle carrier portion of the machine frame (110) for supporting an auxiliary spindle (131) configured to receive and guide a workpiece for parallel machining.

Description

[Technical Field]

[0001] This application relates to machine tools, particularly lathes or turret lathes having an auxiliary or additional spindle arrangement. [Background technology]

[0002] A common type of machine tool, such as a lathe or turret lathe, typically includes a machine frame that may have at least two rotatably mounted work spindles with parallel or coaxial spindle axes facing each other, and the work spindles may receive a workpiece to be machined on the machine tool.

[0003] For example, EP 2714307 relates to a machine tool, in particular a lathe, which comprises a machine frame, a first work spindle arranged on a spindle carrier face of the machine frame to receive a first workpiece, and a second work spindle facing the first work spindle and arranged on the spindle carrier face of the machine frame to receive a second workpiece, the axis of the second work spindle being aligned parallel to, in particular coaxially with, the axis of the first work spindle, and the machine tool comprises two movable tool carrier slides on which respective tool-holding tool carriers are arranged.

[0004] In general, it is required for this type of machine tool to provide a machine tool that allows efficient machining of the workpiece, where possible with as many tools as possible that can be used simultaneously, with as much flexibility as possible regarding the control of the relative movement between the tools and the tool received in the work spindle, with a machine tool design that is at the same time compact, cost-effective but robust, and in a machining area that can be accessed in the best possible way by the machine tool processor or operator. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] European Patent No. 2714307 Summary of the Invention [Problem to be solved by the invention]

[0006] It is an object of the present invention to improve upon machine tools of the general type to overcome the shortcomings of conventional machine tools and to allow for more efficient machining of workpieces, particularly to increase the degree of flexibility for machining workpieces while reducing machining costs. [Means for solving the problem]

[0007] The solution to the problem is proposed with the features of the independent claims. Preferred developments are given in the dependent claims.

[0008] A machine tool according to an exemplary embodiment may be a lathe including a machine frame having an upper tool carrier support portion, a lower tool carrier support portion, and a spindle carrier portion disposed between the upper and lower tool carrier support portions. A spindle carrier may be disposed on or at the level of the spindle carrier portion of the machine frame and support a main spindle configured to receive a workpiece, the main spindle having a horizontally disposed main spindle axis. Multiple tool carriers may be provided, each supported on a tool carrier assembly disposed on either the upper or lower tool carrier support portion of the machine frame. The machine tool may include an auxiliary spindle carrier disposed on the spindle carrier portion of the machine frame and supporting an auxiliary spindle configured to receive and guide a workpiece. Based on this specific configuration having upper and lower tool carrier supports in combination with an auxiliary spindle preferably centrally disposed between the main spindle and the auxiliary spindle, a highly efficient machining system may be provided, thereby simultaneously reducing manufacturing costs.

[0009] The auxiliary spindle carrier can be configured to move the auxiliary spindle along the main spindle axis. The auxiliary spindle can also include at least one direct drive arranged around the guide fixing unit of the auxiliary spindle. Therefore, flexible and efficient machining of the workpiece fixed to the auxiliary spindle can be achieved. Specifically, the auxiliary spindle carrier can be moved closer to the tool carrier assembly, thereby minimizing the processing distance of the tool carrier assembly on the tool carrier support slide.

[0010] The auxiliary spindle can be further configured to secure a workpiece such that two opposing ends of the workpiece can be exposed from the auxiliary spindle for machining operations. The machine tool can be configured to machine at least two workpieces in parallel, with one workpiece secured to the main spindle and one workpiece secured to the auxiliary spindle. Thus, flexible and efficient machining of the workpiece secured to the auxiliary spindle can be achieved. The auxiliary spindle carrier can be rotated and / or moved close to the tool carrier assembly, thereby minimizing the processing distance of the tool carrier assembly on the tool carrier support slide.

[0011] The auxiliary spindle can be configured to rotate about an axis extending perpendicular to the main spindle axis for more flexible machining, while reducing the travel distance of the work tool. The auxiliary spindle can be configured to be movable in a plane including the main spindle axis and a vertical axis orthogonal to the main spindle axis, and the auxiliary spindle can be further configured to be rotatable about an axis extending perpendicular to this plane.

[0012] The auxiliary spindle may include a sleeve that may be electrically, hydraulically and / or pneumatically controlled to securely clamp the workpiece coaxially with the auxiliary spindle axis.

[0013] The auxiliary spindle carrier may be configured to move vertically, perpendicular to the main spindle axis, to move the auxiliary spindle axis of the auxiliary spindle parallel to the main spindle axis.

[0014] The machine tool may include a counter-spindle carrier disposed on a spindle carrier portion of the machine frame and supporting a counter-spindle facing the main spindle and configured to receive a workpiece, the counter-spindle having a horizontally disposed spindle axis disposed coaxially with the main spindle axis.

[0015] The machine tool may further include at least one upper tool carrier assembly mounted on the upper tool carrier support portion and at least one lower tool carrier assembly mounted on the lower tool carrier support portion, both tool assemblies configured to independently machine one or more workpieces housed in the auxiliary spindles.

[0016] The auxiliary spindle may have two opposing sides spaced apart along the auxiliary spindle axis, each side configured to receive a workpiece such that the auxiliary spindle can simultaneously receive two separate workpieces. Each side may have a separate, independent clamping unit for clamping the workpiece. Also, both sides of the auxiliary spindle may be end faces of the auxiliary spindle. The auxiliary spindle may have a first side that is the leftmost side and a second side that is the rightmost side opposite the first side.

[0017] The auxiliary spindle may include a chuck with independently moving jaws for holding irregularly shaped workpieces, preferably the auxiliary spindle includes two separate chucks spaced apart along the auxiliary spindle axis, and / or the auxiliary spindle includes a double cone collet for clamping the workpiece.

[0018] The auxiliary spindle may be mounted to a tool carrier on the upper tool carrier support portion or the lower tool carrier support portion of the machine frame.

[0019] The machine tool may further include two or more upper tool carrier assemblies mounted on (and independently movable with) the upper tool carrier support portion and two or more lower tool carrier assemblies mounted on (and independently movable with) the lower tool carrier support portion, each tool carrier assembly including a tool carrier, the tool carriers configured to independently machine workpieces housed in the auxiliary spindle and / or the main spindle, preferably the tool carriers synchronously machine the workpieces.

[0020] The auxiliary spindle can be configured as a turret unit having a turret disk configured to be rotatable by a first drive means around a disk axis which is the rotation axis of the turret disk, and a second drive means for pivoting the turret head around the turret axis, and preferably the second drive means is a motor having a rotor arranged radially outside the stator.

[0021] The turret disk of the turret unit can be configured to be rotatable about a disk axis, which is the rotation axis of the turret disk, by a first drive means. The turret unit can include a second drive means for pivoting the turret head about the turret axis, and the second drive means can be a motor having a rotor disposed radially outside the stator, and the second drive means can be integrated into the turret body. The turret head can be mounted directly on the rotor of the second drive means.

[0022] The second drive means may be configured to directly drive the turret head to pivot the turret head about the turret axis. The second drive means may be integrated into the turret body such that the cylindrical inner portion of the turret body forms the stator of the second drive means and the cylindrical outer portion of the turret body forms the rotor of the second drive means. The turret disk may be arranged so that the disk axis intersects, preferably perpendicularly, with the rotor magnet of the second drive means. This allows for flexible and efficient machining of workpieces fixed to the auxiliary spindle. The auxiliary spindle carrier may be rotated and / or moved close to the tool carrier assembly, thereby minimizing the processing distance of the tool carrier assembly on the tool carrier support slide.

[0023] A machining method for machining a workpiece using a machine tool may include providing a workpiece to an auxiliary spindle and securing the workpiece to the auxiliary spindle, and machining the secured workpiece from at least one side.

[0024] The method may further include receiving the workpiece from the main spindle and moving the secured workpiece along the main spindle axis to or from the main spindle.

[0025] The machining method may be a bar machining method, and the workpiece to be processed may be loaded through the rear into the main spindle and from the main spindle into the auxiliary spindle and preferably from the auxiliary spindle into the counter spindle.

[0026] The machining method can be a chuck machining method, in which the workpiece to be processed can be fixed to an auxiliary spindle and machined in parallel on two opposite sides.

[0027] The machining method can be configured to machine two or more workpieces simultaneously, with at least one workpiece housed in the auxiliary spindle and one workpiece preferably housed in the main spindle.

[0028] The disclosure of European Patent Application No. 18191544.8 (EP 3616832) is incorporated herein by reference.

[0029] Those skilled in the art will appreciate that various adaptations, modifications, and / or combinations of the aspects just described may be constructed. Accordingly, it should be understood that additional aspects may be practiced other than as specifically described herein. In light of the present disclosure, those skilled in the art will also appreciate that different aspects described herein may be combined to form other aspects of the present disclosure. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is a diagram illustrating an example of the schematic structure of a multi-spindle lathe in which an auxiliary spindle is arranged in the center. [Figure 2] FIG. 1 is a diagram illustrating a schematic perspective view of a multi-spindle lathe. [Figure 3] FIG. 10 is another schematic perspective view of a multi-spindle lathe including a turret unit, for example. [Figure 4] FIG. 1 is an exemplary diagram illustrating a schematic of a tool carrier assembly. [Figure 5] FIG. 2 shows an exemplary cross section through the machine frame. [Figure 6a] FIG. 1 is a perspective view of a multi-spindle lathe. [Figure 6b] FIG. 1 is an exemplary perspective view of a multi-spindle lathe including a turret unit and an auxiliary spindle. [Figure 7] 10A and 10B are exemplary diagrams illustrating an auxiliary spindle mounted on a tool carrier support slide. [Figure 8] FIG. 10 is a diagram illustrating an example of a turret unit and a movable auxiliary spindle that can be independently mounted on a machine tool. [Figure 9] FIG. 10 is a diagram showing an example of an arrangement for bar processing. [Figure 10] FIG. 10 is a diagram showing an example of an arrangement for chucking. [Figure 11] FIG. 10 is a diagram illustrating an example cross-sectional view of an auxiliary spindle. [Figure 12] 1 is a schematic perspective view of a multi-spindle lathe having four similar turret units and an exemplary diagram showing details of the turret units. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0031] In the following, preferred aspects and embodiments will be described in more detail with reference to the accompanying drawings. The same or similar features in different drawings and embodiments are referred to by like reference numerals. It should be understood that the following detailed description of various preferred aspects and embodiments is not meant to limit the scope of the present invention.

[0032] FIG. 1 illustrates an exemplary configuration according to the present invention. Specifically, an auxiliary spindle carrier 130 is provided having an auxiliary spindle 131 disposed between a main spindle 121 and a counter spindle 141. The main spindle 121 has a horizontal axis HA, and a vertical axis (of the main spindle) is shown as VA. In the embodiment illustrated in FIG. 1, separate workpieces W are secured to each of the main spindle, auxiliary spindle, and counter spindle for synchronous machining.

[0033] Specifically, a workpiece W is fixed in the main spindle 121. This workpiece can be machined by a tool provided on a tool carrier. In FIG. 1, for example, two turret units T are provided, which are mounted on respective tool carrier support slides 151 so that these carrier support slides can move parallel to the horizontal axis HA. However, two tool carrier assemblies, specifically turret units T vertically above and below the horizontal axis HA, are merely exemplary, and it is clear that in further developments, four tool carrier assemblies can be used to further increase the machining flexibility of the machine tool. Adjacent to the main spindle 121 carrying the workpiece W, an auxiliary spindle 131 is provided. This auxiliary spindle 131 carries a workpiece W fixed to a respective workpiece fixing unit. The auxiliary spindle 131 has a very special configuration according to the embodiment shown in FIG. 1. Specifically, the auxiliary spindle 131 is attached to an auxiliary spindle carrier 130 and is configured to be movable along the vertical and horizontal axes VA and HA.

[0034] Flexibility can be further enhanced by enabling rotational or pivotal movement of the auxiliary spindle 131 along an axis perpendicular to the plane established by the horizontal axis HA and the vertical axis VA. See also the rotation arrow in FIG. 1 , which indicates the rotational movement of the auxiliary spindle 131. This rotational movement enables the auxiliary spindle 131 to rotate the fixed workpiece W, thus rotating the auxiliary spindle axis XA to apply an angle between the auxiliary spindle axis XA and the horizontal axis HA. Flexible and efficient machining of the workpiece fixed to the auxiliary spindle 131 can thus be achieved. In particular, the auxiliary spindle carrier 130 with the workpiece W can be moved closer to the tool carrier assembly, thereby minimizing the processing distance of the tool carrier assembly on the tool carrier support slide 151.

[0035] As shown, tool assembly 150 may include, but is not limited to, a turret unit T, such as that shown in Figure 1. However, by providing turret unit T with a turret disk with multiple slots for mounting tools, the processing flexibility of the machine tool, specifically the lathe, can be maximized.

[0036] Furthermore, the movement and rotation of the auxiliary spindle 131 and auxiliary spindle carrier 130 can be independent of the movement of the main spindle 121, the counter spindle 141, and the tool carrier support slide 151 with each tool carrier assembly 150. One particularly useful embodiment includes a main spindle 121 that can provide a workpiece via bar feeding along the central axis of the main spindle, i.e., the horizontal axis HA. The provided workpiece can be machined at its front end by one or two tools on each tool carrier assembly attached to the tool carrier support slide 151, or by respective tools on a turret unit T vertically above or below the horizontal axis HA. In a next step, after the front end of the workpiece has been machined, the workpiece can be secured to the auxiliary spindle 131 by moving the auxiliary spindle carrier 130 together with the auxiliary spindle 131 to the main spindle and inserting the workpiece into the auxiliary spindle 131.

[0037] During the process of receiving a workpiece by the auxiliary spindle 131 from the main spindle 121, the horizontal axis HA is coaxial with the auxiliary spindle axis XA to allow for smooth insertion of the workpiece W. After the workpiece is inserted into the auxiliary spindle 131, the rear end of the workpiece can be separated from the raw workpiece material contained in the main spindle 121. Thereafter, the auxiliary spindle 131 with the workpiece W fixed along the auxiliary spindle axis XA can be moved away from the main spindle 121 for further processing of the front end and / or the rear end of the workpiece W fixed on the auxiliary spindle 131.

[0038] As shown exemplarily in FIG. 1 , the front end of a workpiece W fixed to the auxiliary spindle 131 is machined by a turret unit T mounted below the horizontal axis HA and thus vertically below the horizontal axis. Simultaneously, the rear end of the workpiece W fixed to the auxiliary spindle 131 can be machined by a turret unit T mounted above the horizontal axis HA, i.e., vertically above the main spindle in FIG. 1 . Therefore, in such a configuration, both ends of the workpiece on the auxiliary spindle 131 can be processed simultaneously. This has the advantage that the workpiece can be clamped only once, reducing errors caused by clamping the workpiece more than once. Therefore, both sides of the workpiece can be machined. Greater flexibility can be achieved by providing a drive unit integrated into the turret unit to drive a tool attached or received in the tool mounting position of the turret unit T. For example, in FIG. 1 , each turret unit has a drill or milling cutter as a tool for processing the workpiece W.

[0039] It is also possible to process a workpiece on the auxiliary spindle 131 while simultaneously processing the front end of a new workpiece W provided to the main spindle 121. As shown in Figure 1, for example, the lower turret unit machines the workpiece on the auxiliary spindle 131, while the turret unit T vertically above the main spindle can move towards the workpiece on the main spindle 121 to machine the front end of each workpiece. The particular flexibility provided by the special structure of this embodiment allows for improved, cost-effective serial production of workpieces.

[0040] In addition to the workpieces in the main spindle 121 and the auxiliary spindle 131, and as shown in FIG. 1, a further workpiece can then be included in the counter spindle 141. The rear end of the workpiece can then be processed in the counter spindle, while the workpiece in the main spindle 121 or the auxiliary spindle 131 can also be machined. Thus, even very complex workpieces can be machined in an industrial serial production process by using the machine tool of this embodiment. Also, by providing an additional B-axis movement in the turret unit T, maximum flexibility and cost-effective production can be achieved. Such B-axis movement may enable the turret head to move around the longitudinal axis of the turret body, for example, as shown in FIG. 12.

[0041] Figure 2 exemplarily shows a schematic perspective view of the machine frame 110 of the machine tool according to Figure 1. The machine frame 110 exemplarily stands on two machine stand parts 111a and 111b, and a carrier support part of the machine frame 110 exemplarily is formed between and held by the machine stand parts 111a and 111b.

[0042] The machine frame 110 illustratively has an upper support portion 113 and a lower support portion 114, both of which illustratively extend horizontally between the two machine stand portions 111 a and 111 b. A front support portion 112 of the machine frame 110 is formed between the upper support portion 113 and the lower support portion 114, and the front support portion 112 extends horizontally between the two machine stand portions 111 a and 111 b.

[0043] The front support portion 112 of the machine frame 110 illustratively has a vertically disposed front surface. The upper surface of the upper support portion 113 of the machine frame 110 is disposed on an inclined slope, illustratively at an inclination angle of substantially 45 degrees (e.g., relative to the work floor on which the machine frame 110 stands with its machine stand portions 111a and 111b). The lower surface of the lower support portion 114 of the machine frame 110 is disposed on an overhanging inclined slope, illustratively at an inclination angle of substantially 315 degrees (e.g., relative to the work floor on which the machine frame 110 stands with its machine stand portions 111a and 111b).

[0044] In another exemplary embodiment, the inclination angle of the upper surface of the upper support portion 113 of the machine frame 110 may be in the range of 30 to 60 degrees. Also, the inclination angle of the lower surface of the lower support portion 114 of the machine frame 110 may be in the range of 300 to 330 degrees. Specifically, it may be specified that the angle formed between the upper and lower support portions 113 and 114 is preferably substantially 90 degrees.

[0045] The upper support portion 113 of the machine frame 110 has horizontally extending guides 113a for slidably supporting the tool carrier assembly 150 on the upper side of the machine frame 110 in the machining area between the spindles. The lower support portion 114 of the machine frame 110 has horizontally extending guides 114a for slidably supporting the tool carrier assembly 150 on the lower side of the machine frame 110 in the machining area between the spindles. The front support portion 112 oriented toward the front of the machine frame 110 has horizontally extending guides 112a for slidably supporting the counter spindle carrier 140 and the auxiliary spindle carrier 130.

[0046] 3 is another diagram of a machine tool equipped with a tool carrier assembly 150. In the illustrated example, four separate tool carrier assemblies 150 are provided at four separate positions independent of one another. Preferably, the tool carriers provided for the tool carrier assemblies are identical and are mounted with a 90-degree or 180-degree twist, for example. The auxiliary spindle carrier 130 is provided between the main spindle carrier with the main spindle 121 and the counter spindle carrier 140 with the counter spindle 141. The tool carrier assemblies 150 are provided on the upper support part 113, vertically above the horizontal axis HA. The tool carrier assemblies 150 are provided on the lower support part 114, below the horizontal axis HA.

[0047] An example of a tool carrier assembly 150 is shown in Figure 4, mounted on carrier support slides 151. Each carrier support slide 151 is capable of horizontal movement along a horizontal axis HA. Tool carrier support slides 152 allow vertical movement along a vertical axis VA. A turret or tool carrier quill 153 may be provided mounted on the carrier support slides 152.

[0048] The tool carrier assembly 150 includes a carrier support slide 151 configured to be slidably mounted in guides 113a or 114a of the upper and lower support portions 113 or 114 of the machine frame 110. Thus, when mounted on guides 113a atop the upper support portion 113, the carrier support slide 151 is configured to move horizontally on and along guides 113a in a horizontal direction parallel to the horizontally and coaxially aligned spindle axes of the spindles 121 and 141. On the other hand, when mounted in a suspended manner on guides 114a on the overhanging lower support portion 114, the carrier support slide 151 is configured to move horizontally along guides 114a in a horizontal direction parallel to the horizontally and coaxially aligned spindle axes of the spindles 121 and 141.

[0049] On the front side of carrier support slide 151 of tool carrier assembly 150, facing the machining area of ​​machine tool 100 between spindles 121 and 141, tool carrier support slide 152 is slidably mounted on carrier support slide 151. Tool carrier support slide 152 is configured to move vertically on and along a vertical guide disposed vertically on the front surface of carrier support slide 151.

[0050] At the front side of the tool carrier support slide 152 of the tool carrier assembly 150, facing the machining area of ​​the machine tool 100 between the spindles 121 and 141, a horizontally positioned tool carrier quill is illustratively provided that extends vertically from the front side of the tool carrier support slide 152 into the machining area of ​​the machine tool 100 so as to mount a tool carrier at the front end of the tool carrier quill 153.

[0051] In an exemplary embodiment, optionally, the tool carrier quill may be mounted on a tool carrier support slide 152 for controllable movement horizontally toward the front of the machine tool 100 in a direction perpendicular to the direction of the spindle axes of the spindles 121 and 141.

[0052] In accordance with the above configuration, tool carrier assembly 150 is configured to hold a tool carrier or turret unit T, e.g., a tool holder for holding one or more tools, and is further configured to controllably move the tool carrier in three independent directions of movement, including a direction vertically and extending perpendicular to the horizontal orientation of the spindle axis, a direction horizontally and extending perpendicular to the horizontal orientation of the spindle axis, and a Z direction horizontally and extending parallel to the horizontal orientation of the spindle axis. Thus, tool carrier assembly 150 is illustratively configured with three independently controllable linear axes.

[0053] Additionally, optionally, the tool carrier quill may be configured to further include a B-axis that is rotatably driven to control the rotational movement of the tool carrier mounted on the tool carrier assembly 150 about the horizontally positioned longitudinal axis of the tool carrier quill.

[0054] Figure 5 exemplarily shows a schematic cross-sectional view through machine frame 110 of machine tool 100 of Figure 2. The cross-sectional shape of machine frame 110 of machine tool 100 exemplarily comprises the shape of an isosceles equiangular trapezoid rotated 90 degrees. In other embodiments, the shape may be different and the angle of rotation may be different.

[0055] 5 shows that the front support portion 112 of the machine frame 110 exemplarily has a vertically disposed front surface. The spindle carrier case 120 is mounted to the front side of the machine tool 100 at the height of the front support portion 112. The front support portion 112 further supports a horizontally extending guide 112a, on which the counter spindle carrier 140 and / or the auxiliary spindle carrier 130 can be slidably mounted (not shown in FIG. 5).

[0056] As previously mentioned, the upper surface of upper support portion 113 of machine frame 110 is disposed on an inclined slope, illustratively at an inclination angle of substantially 45 degrees (e.g., relative to the work floor on which machine frame 110 stands with its machine stand portions 111a and 111b). As previously mentioned, in other exemplary embodiments, the inclination angle of the upper surface of upper support portion 113 of machine frame 110 can be in the range of 30 to 60 degrees.

[0057] To slidably support the tool carrier assembly 150 above the machine frame 110 in the machining area between the spindles, the upper support portion 113 of the machine frame 110 has horizontally extending guides 113a on which the upper tool carrier assembly 150 is mounted. The upper tool carrier assembly 150 can move horizontally and parallel to the direction of the spindle axes (i.e., perpendicular to the plane of the drawing in Figure 5).

[0058] The lower surface of the lower support portion 114 of the machine frame 110 is disposed on an overhanging inclined slope, illustratively at an inclination angle of substantially 315 degrees (e.g., relative to the work floor on which the machine frame 110 stands with its machine stand portions 111a and 111b). The inclination angle of the lower surface of the lower support portion 114 of the machine frame 110 may be in the range of 300 to 330 degrees. Specifically, it may be specified that the angle formed between the upper and lower support portions 113 and 114 is preferably substantially 90 degrees.

[0059] To slidably support the tool carrier assembly 150 in a suspended state beneath the machine frame 110 in the machining area between the spindles, the lower support portion 114 of the machine frame 110 has horizontally extending guides 114a on which the lower tool carrier assembly 150 is suspended. The lower tool carrier assembly 150 can move horizontally and parallel to the direction of the spindle axis (i.e., perpendicular to the plane of the drawing in FIG. 5).

[0060] As can be seen in FIG. 5 , the advantage of having the lower surface of the lower support portion 114 of the machine frame 110 positioned on an overhanging sloping slope to support and hold the lower tool carrier assembly 150 in a suspended state is that the slide and support structure of the lower tool carrier assembly 150 can be hidden under the overhanging lower support portion 114 so that it does not extend into the machining area under the spindle, and therefore chips that fall from the workpiece during machining can fall unhindered by the support structure of the lower tool carrier assembly 150.

[0061] Illustratively, in FIG. 5, an upper tool carrier assembly 150 holds a tool turret 1 and a lower tool carrier assembly 150 holds a machining head 2 which holds and drives a tool such as a grinding tool or milling cutter.

[0062] 6a and 6b show an exemplary configuration of a machine tool according to an embodiment of the present invention. An upper-left tool carrier assembly 150a and an upper-right tool carrier assembly 150b are provided vertically above a horizontal axis HA. A main spindle carrier 120 having a mounting portion for mounting a main spindle 121 is provided in the center of the front support portion of the machine tool. An auxiliary spindle carrier 130 is provided so as to be movable between the main spindle carrier 120 and the counter-spindle carrier 140. A lower-left tool carrier assembly 150c is provided vertically below the horizontal axis HA. A lower-right tool carrier assembly 150d is also provided below the horizontal axis HA. Each of the upper and lower tool carrier assemblies 150a-150d is movable horizontally and vertically along support surfaces provided by the horizontal and vertical axes, as shown in FIG. 6a.

[0063] In FIG. 6b, each turret unit is illustratively mounted on a tool carrier assembly. Turret unit T preferably includes a turret disk with multiple slots for mounting multiple tools for machining the workpiece. With the specific configuration shown in FIG. 6, a highly flexible and efficient machining system, specifically a multi-spindle lathe, can be provided for simultaneously machining multiple workpieces using different tools. Another advantage is the symmetrical design of the turret units used in the lathe. Specifically, the same type of turret unit T can be provided for four separate assembly positions on the tool carrier assemblies 150a-150d, and the turret units are designed with symmetrical bodies so that the turret head can be rotated appropriately depending on the respective positions of the turret units. Therefore, a highly efficient and easy-to-maintain structure can be achieved, which simultaneously enables flexible and cost-effective machining of workpieces.

[0064] A further embodiment is shown, for example, in FIG. 7 , in which the auxiliary spindle 131 is mounted on the upper left tool carrier assembly 150a via an angled carrier unit 131. However, it will be apparent that other positions on the tool carrier assembly 150 may also be suitable for providing the auxiliary spindle 131 mounted via the angled carrier 131a. By providing this particular configuration, it is possible to provide an auxiliary spindle 131 that is movable in both vertical and horizontal directions. It is also possible to provide multiple auxiliary spindles 131, for example, two separate auxiliary spindles 131 each on the upper and / or lower tool carrier assemblies 150. This allows for greater flexibility in machining workpieces, and the tool carrier assemblies 150 can be used synergistically for different operations, enabling improved serial production of complex workpieces.

[0065] 8a-8d illustrate an example of the application of an auxiliary / additional spindle 131 to a machine tool, and specifically to a tool carrier assembly of the machine tool. The specific configuration shown in FIG. 8a can simultaneously machine multiple workpieces using different tools, providing a highly flexible and efficient machining system, specifically a multi-spindle lathe. The auxiliary spindle 131 can be configured to be movable between the main spindle carrier 120 and the counter-spindle carrier 140, and additionally, vertically, as shown in FIG. 8b. The auxiliary spindle also has an auxiliary spindle axis XA and is mounted on an auxiliary spindle carrier that is disposed on a tool carrier support portion for increased flexibility. A lower-left tool carrier assembly 150 is provided vertically below the horizontal axis. A lower-right tool carrier assembly 150 is also provided below the horizontal axis. Each of the upper and lower tool carrier assemblies is preferably movable horizontally and vertically. As is apparent from FIGS. 8c and 8d, one or more of the tool carrier and / or auxiliary spindles can be configured to include a rotatably driven B-axis for controlling the rotational movement of the tool carrier and / or auxiliary spindle about its horizontally arranged longitudinal axis. Providing an additional spindle according to the present invention also allows machining of workpieces without a primary or counter spindle, since machining can be performed using only the additional spindle. Highly efficient machining has been achieved by combining an auxiliary / additional spindle 131 with B-axis movement and at least one turret unit also with B-axis movement. Thus, both the turret unit and the auxiliary spindle can be rotated (independently) about axes perpendicular to their respective spindle axes. This combination allows for an increased maximum angle between the workpiece on the auxiliary spindle and the tool (e.g., the turret unit) of the head. In a further development, all turret units have B-axis movement.

[0066] FIG. 9 illustrates an optimized machining process using a machine tool according to the present invention. In the upper left diagram, a bar-feeding process is shown using a main spindle MS, an auxiliary spindle AS, and a counter spindle CS. As shown, two separate tools are provided for machining a workpiece fixed to the auxiliary spindle AS (131) from one side. The raw material for the workpiece is fed through the main spindle MS. Thus, in the first operational step, machining of the front end of the workpiece fixed to the auxiliary spindle AS is achieved. To machine the rear end of the workpiece, the auxiliary spindle AS moves the workpiece along the horizontal axis to the fixed unit of the counter spindle. As shown in FIG. 9, in the upper left diagram, referred to as a Swiss-type, the workpiece can then be machined from its rear end while still fixed to the fixed portion of the counter spindle. Therefore, this can be considered the second operational step, and therefore the second machining step, for producing each workpiece. After machining the workpiece, it can be removed from the counter spindle upon completion.

[0067] As shown in the top right diagram in FIG. 9, also referred to as AS (without CS), the additional spindle 131 is equipped with a double-cone collet to preferably synchronously enable machining at the front and rear ends of a workpiece fixed on the auxiliary spindle. At the same time, machining of the next workpiece, still on the main spindle, is already possible. Thus, each configuration allows for the simultaneous processing of two separate workpieces, one of which can be processed simultaneously on both sides. After finishing machining in the second operating step, the finished part can be removed from the auxiliary spindle.

[0068] A further development is provided, for example, in the lower left part of FIG. 9 , referred to as AS+CS. Thus, a main spindle is provided with an auxiliary spindle and a counter spindle. In a first operational step, workpieces fed by bar feeding along its central axis through the main spindle can be processed at their front ends. In a second operational step, the auxiliary spindle clamps each workpiece, enabling processing of the front and rear ends of the clamped workpiece, preferably simultaneously. Thus, when the workpiece is clamped on the auxiliary unit, the front and rear ends of the workpiece can be processed simultaneously. The auxiliary spindle can be moved along a horizontal axis to transfer the workpiece from the main spindle to the counter spindle. In a third operational step, the workpiece contained in the counter spindle can be processed independently of the auxiliary spindle or the workpiece contained in the main spindle. The finished part can then be provided from the machining area of ​​the machine tool through the central axis of the counter spindle. Thus, a highly efficient and cost-effective machining process can be achieved.

[0069] In the lower right diagram of FIG. 9 , also referred to as AS cross + CS, a flexible auxiliary spindle 131 is provided. This auxiliary spindle is movable in both horizontal and vertical directions, i.e., along a horizontal axis HA and a vertical axis VA perpendicular to the horizontal axis. A workpiece is fed through the central axis of the main spindle and can be processed at its front end in a first operational step, as shown in the lower right diagram. In a second operational step, the movable counter spindle picks up the workpiece from the main spindle, allowing processing of the workpiece's rear end, as shown in the diagram. The processed workpiece can then be contained and fixed in the auxiliary spindle, so that, for example, the auxiliary spindle can move vertically and horizontally to receive the machined workpiece from the counter spindle, and then the auxiliary spindle can move away from the horizontal axis to allow movement of the counter spindle CS in the horizontal axis for further machining of the workpiece. Therefore, as shown in the diagram, synchronous machining of workpieces on the main spindle MS, the counter spindle, and the auxiliary spindle is possible. This is primarily achieved by providing flexible movement of the auxiliary spindle 131, which can move vertically and horizontally. The finished workpiece can be removed from the machining area by the auxiliary spindle in an appropriate manner. As a clamping unit, two separate chucks are provided so that the auxiliary spindle AS can firmly clamp each workpiece.

[0070] A more specific example is shown in Figure 10, which illustrates chuck machining using an auxiliary spindle AS as described above. As shown in the top left diagram of Figure 10, designated AS only, processing the auxiliary spindle involves four separate tools, preferably Parallel The auxiliary spindle is preferably movable at least horizontally and can be provided with a double cone collet to easily provide a firm fixation of the workpiece, thereby enabling high precision machining of the workpiece and easy loading and unloading.

[0071] In a further configuration, as shown in the upper right portion of Figure 10, designated Figure MS+AS+CS, the auxiliary spindle is horizontally movable and has two separate clamping units. A main spindle and an opposing spindle are also provided, with the opposing spindle being horizontally movable. In each of these figures, four separate workpieces are processed simultaneously. Specifically, the front end of a workpiece clamped to the main spindle can be processed in U1. A second workpiece clamped to the left clamping unit of the auxiliary spindle is processed in a second operation U2. Simultaneously, the front end of a third workpiece clamped to the right clamping unit of the auxiliary unit can also be processed in U4 during the second operation. Finally, a fourth workpiece clamped to the opposing spindle can also be processed in U3. Therefore, this particular configuration achieves both very high workpiece output and high-precision machining. In the lower left portion of Figure 10, designated Figure MS+AS+CS, the auxiliary spindle includes a double-cone collet to further improve clamping.

[0072] In the lower right portion of FIG. 10, designated as MS+AS+CS, additional rotary guide bushings or steady rests are provided to further enhance the machining flexibility of the multi-spindle lathe.

[0073] 11 exemplarily shows a cross-sectional view of an auxiliary hollow spindle 131 according to an exemplary embodiment. The auxiliary (hollow) spindle 131 includes a direct drive 132 arranged around a guide fixing unit including a sleeve 133 that can be electrically, hydraulically, and / or pneumatically controlled to firmly fix the workpiece W coaxially with the spindle axis in a second fixed state, with both ends of the workpiece W extending from the auxiliary hollow spindle 131 and exposed for machine operations to be performed simultaneously on both ends. In addition to the above exemplary embodiments, further exemplary embodiments are contemplated.

[0074] For example, in other exemplary embodiments, the machine tool may further include an auxiliary spindle carrier arranged on the upper or lower tool carrier portion of the machine frame and supporting an auxiliary hollow spindle configured to receive and guide a workpiece coaxially with the spindle axis of the main spindle, in particular so that the workpiece extends from the auxiliary hollow spindle on both sides of the auxiliary spindle carrier, in particular so that a workpiece clamped by the auxiliary hollow spindle can be machined without releasing the clamping.

[0075] For example, the auxiliary spindle carrier may be configured to move along horizontal guides located on the upper or lower tool carrier portion of the machine frame in a horizontal direction parallel to the spindle axis of the primary spindle.

[0076] Also in such exemplary embodiments, the auxiliary spindle carrier can be disposed between the primary spindle carrier and the counter spindle carrier, and in such exemplary embodiments, the auxiliary spindle carrier can support a spindle slide that supports the auxiliary hollow spindle to drive movement of the auxiliary hollow spindle laterally or perpendicularly to the spindle axis.

[0077] In a further exemplary embodiment, the machine tool may include two auxiliary hollow spindles, for example one positioned opposite the main spindle and one positioned opposite the counter spindle, preferably both auxiliary hollow spindles being positioned between the main and counter spindles.

[0078] For example, both auxiliary hollow spindles may be configured to move horizontally in the direction of the spindle axis, and the two auxiliary hollow spindles may each be configured as discussed above for the single auxiliary hollow spindle.

[0079] Specifically, both auxiliary spindle carriers can be positioned on the spindle carrier portion. Additionally, each of the auxiliary spindle carriers can be positioned on the spindle carrier portion, the upper and / or the lower tool carrier portion. In some exemplary embodiments, one auxiliary spindle carrier can be positioned on the upper tool carrier portion, and the other auxiliary spindle carrier can be positioned on the lower tool carrier portion. Furthermore, one or both of the auxiliary hollow spindles can be configured to move laterally or vertically relative to the spindle axis.

[0080] FIG. 12 shows an exemplary configuration of a lathe L having four similar turret units T, each of which has a B-axis movement function that allows the turret head H to rotate about the turret body axis M.

[0081] As shown on the left side of FIG. 12, the turret unit T has a compact design due to its inverse motor configuration and gearless torque transmission. The turret unit T includes a turret body M that can be attached to a tool carrier assembly 150 via a mounting portion M1 on the turret body. The mounting portion M1 is located on the rear side of the turret body M, the opposite side of which can be referred to as the front side of the body M and is the free end of the turret body M. While conventional turret units include a turret body separated from a drive means for controlling the pivoting of the turret head H about the B-axis or Y-axis, the present invention proposes an integrated drive means, referred to as a second drive means D2. The second drive means B2 is integrally formed on the turret body M as a structural part thereof. Thus, the outer cylindrical portion of the turret body M and the inner cylindrical portion of the turret body M are respectively designed as the actual rotor and stator of the second drive means D2. As shown on the left side of FIG. 12, the outer cylindrical portion of the turret body M is rotatable about the Y-axis. This movement is commonly referred to as B-axis movement.

[0082] In the example shown in Figure 12, the Y-axis, which is the rotation axis of the turret body (or turret rotation axis), extends perpendicular to the spindle axis of the main spindle. To change the position of the turret head, B-axis movement is integrated into the lathe, thereby allowing the turret head H and turret disk H2 to be rotated about the Y-axis, thereby allowing different tools or workpieces mounted on the turret disk H2 to be flexibly positioned with respect to the main or auxiliary spindles, enabling flexible and efficient machining of workpieces. The lathe according to the present invention is also superior to conventional lathes because the tool carrier assembly allows vertical and horizontal movement of the turret unit T, and in combination with the turret unit T allowing B-axis movement, very efficient processing of workpieces can be achieved.

[0083] As is clear from FIG. 12, the turret head H includes a turret head base H1 and a turret disk H2. The turret disk H2 has a rotation axis X. The turret disk H2 is configured to rotate about said turret disk rotation axis X. The rotating turret disk H2 has slots for machine tools and / or workpieces. The turret disk H2 also has an integrated third drive means D3 that makes it possible to drive a tool attached or inserted in the slot of the turret disk H2. Preferably, the third drive means is a direct drive motor.

[0084] The turret disk H2 extends radially in the Y-axis direction of the turret body M. Therefore, the turret disk H2 is disposed radially outside the turret body M. In the axial direction of the Y-axis of the turret body M, the turret head H does not extend farther than the free end of the turret body M. The turret head H extends in the axial direction of the Y-axis of the turret body M almost to the end face of the free end of the turret body M. Therefore, a very efficient and compact design can be achieved, and the distance between the turret disk H2 and the mounting portion M1 of the turret body can be minimized. The inventors have realized that this specific design can greatly increase the mechanical stability and precision of the turret unit and the entire lathe L.

[0085] The turret head H has a flat turret design, with the base H1 of the turret head H being flat. A turret disk H2 is rotatably mounted on the base H1. The turret disk H2 is rotatable about the X-axis, which is preferably substantially perpendicular to the Y-axis of the turret body M. To further flatten the turret head H, an additional drive means required to rotate the turret disk H2 is located on top of the turret head base H1 as a first drive means D1, which covers a portion of the outer cylindrical shaft of the turret body M. The first drive means D1 extends away from the turret disk H2 along the X-axis. The turret head base H1, to which the first drive means D1 is attached, forms an L-shape surrounding the turret body M, thereby achieving a vibration-resistant, compact turret unit T that can be flexibly mounted to different tool carrier assembly positions on a lathe L or machine tool. The radially outer peripheral surface of the turret body M is therefore the mounting surface for the turret head H, and this turret head H can be mounted radially spaced apart from the turret rotation axis Y.

[0086] It should be noted that, in general, workpieces can be loaded into the machine tool by a workpiece loading device such as a bar loader, a bar feeder, and / or a handling robot. The machined workpiece can be removed by an unloading device, for example by a handling robot.

[0087] While several exemplary embodiments have been described above, it should be understood that such embodiments are merely illustrative of the broad invention, not limiting thereto, and that the exemplary embodiments are not limited to the specific constructions and arrangements shown and described above, as various other changes, combinations, omissions, modifications, and substitutions are possible in addition to those described in the preceding paragraphs. Those skilled in the art will appreciate that various adaptations, modifications, and / or combinations of the embodiments just described can be constructed. Thus, it should be understood that additional embodiments other than those specifically described herein can be practiced. In light of the present disclosure, those skilled in the art will also appreciate that different embodiments described herein can be combined to form other embodiments of the present disclosure.

[0088] The following aspects of the present invention are also described.

[0089] According to one embodiment for the machine tool, the lower surface of the lower tool carrier support portion is inclined at an overhang angle in the range between 300 and 330 degrees, in particular substantially 315 degrees.

[0090] According to one aspect of the machine tool, an upper surface of an upper tool carrier support portion, on which one or more tool carriers can be mounted, is arranged to have an incline.

[0091] According to one embodiment for the machine tool, the upper surface of the upper tool carrier support portion is inclined at an angle of inclination in the range between 30 and 60 degrees, in particular substantially 45 degrees.

[0092] According to one aspect for the machine tool, the or each tool carrier assembly is configured to independently move each tool carrier in one or more linear directions, including at least one of a Z-axis direction of movement for horizontally moving the tool carrier in a direction parallel to the spindle axis of the main spindle, an X-axis direction of movement for radially moving the tool carrier relative to the spindle axis of the main spindle, and a Y-axis direction of movement for moving the tool carrier in a direction perpendicular to the spindle axis of the main spindle and perpendicular to the X-axis movement of the main spindle.

[0093] According to one aspect for the machine tool, one or more or each tool carrier assembly is configured to rotate the respective tool carrier about an axis of rotation extending perpendicular to the spindle axis of the main spindle, particularly by B-axis movement.

[0094] According to one aspect for a machine tool, the main spindle carrier and / or the counter spindle carrier are configured to move in a horizontal direction parallel to the spindle axes of the main and counter spindles along horizontal guides located on the spindle carrier portion of the machine frame.

[0095] According to one aspect for a machine tool, an opposing spindle carrier supports a spindle slide that supports an opposing spindle to drive movement of the opposing spindle laterally or perpendicularly to the spindle axis.

[0096] According to one aspect for a machine tool, the auxiliary spindle carrier is configured to move in a horizontal direction parallel to the spindle axis of the main spindle along a horizontal guide located on the spindle carrier portion of the machine frame.

[0097] According to one aspect for a machine tool, the auxiliary spindle carrier is disposed between the main spindle carrier and the counter spindle carrier.

[0098] According to one aspect for a machine tool, the auxiliary hollow spindle includes an electrically, hydraulically and / or pneumatically controlled clamping unit that clamps a workpiece received on the auxiliary hollow spindle, and a drive that drives a rotational movement of the workpiece clamped by the clamping unit.

[0099] According to one aspect for a machine tool, the drive includes an electric or electromagnetic direct drive mechanism.

[0100] According to one aspect for a machine tool, an auxiliary spindle carrier supports a spindle slide that supports an auxiliary hollow spindle to drive movement of the auxiliary hollow spindle laterally or perpendicularly to the spindle axis.

[0101] The exemplary embodiments and aspects as described above suggest further advantageous aspects and features that enhance the machining options of turret units and machine tools, in particular lathes, to provide cost-effective machining concepts, enable more flexible, accurate, efficient and reliable machine operations, and / or improve the accuracy and / or stability of the machine tools.

[0102] While several exemplary embodiments and / or aspects have been described and illustrated in the accompanying drawings, it is to be understood that such embodiments and aspects are merely illustrative of the broad invention, and not limiting thereto, and that embodiments of the invention are not limited to the specific constructions and arrangements shown and described, as various other changes, combinations, omissions, modifications, and substitutions are possible in addition to those described in the above sections.

[0103] Those skilled in the art will appreciate that various adaptations, modifications, and / or combinations of the presently described embodiments can be made without departing from the scope of the present disclosure. In light of the present disclosure, those skilled in the art will also appreciate that different embodiments of the present invention described herein can be combined to form other embodiments of the present invention. It is therefore to be understood that the present invention can be practiced other than as specifically described herein.

Claims

1. A machine tool, in particular a lathe, a machine frame (110) having a tool carrier support portion and a spindle carrier portion for holding a spindle; at least one tool carrier supported on a tool carrier assembly (150) disposed on a tool carrier support portion of the machine frame (110); Equipped with an auxiliary spindle carrier (130) supporting an auxiliary spindle (131) having an auxiliary spindle axis (XA), the auxiliary spindle carrier (130) being arranged on the spindle carrier part of the machine frame (110) or on the tool carrier support part; the auxiliary spindle (131) is configured to fix the workpiece (W) so that the workpiece (W) can be exposed from two opposite sides of the auxiliary spindle (131) for performing machining operations on both ends of the workpiece (W), and is configured to rotate about an axis extending perpendicular to the auxiliary spindle axis (XA); Machine tools.

2. 2. The machine tool of claim 1, wherein the auxiliary spindle (131) is a hollow spindle having at least two sides, each side configured to receive the workpiece, and the sides of the at least two sides are spaced apart from one another along the auxiliary spindle axis (XA).

3. 3. The machine tool according to claim 1 or 2, wherein the auxiliary spindle (131) comprises at least one direct drive arranged around a guide fixing unit of the auxiliary spindle (131).

4. The machine tool according to any one of claims 1 to 3, wherein the machine tool is configured for parallel machining of two workpieces (W) fixed in the auxiliary spindle (131).

5. 5. The machine tool according to claim 1, further comprising a spindle carrier arranged on or at the level of the spindle carrier part of the machine frame (110) and supporting a main spindle (121) configured to receive a workpiece, the main spindle (121) having a horizontally arranged main spindle axis (HA), and / or the auxiliary spindle carrier (130) configured to move the auxiliary spindle (131) along the main spindle axis (HA) and also orthogonal to the main spindle axis (HA).

6. 6. The machine tool according to claim 1, wherein the auxiliary spindle (131) comprises one or more sleeves (133) which can be independently controlled to electrically, hydraulically and / or pneumatically fix the workpiece (W) coaxially with the auxiliary spindle axis (XA).

7. 6. The machine tool according to claim 5, further comprising: a counter-spindle carrier (140) arranged on the spindle carrier portion of the machine frame (110) and supporting a counter-spindle (141) facing the main spindle (121) and configured to receive a workpiece (W), the counter-spindle (141) having a horizontally disposed spindle axis arranged coaxially with the main spindle axis (HA).

8. 8. The machine tool according to claim 1, comprising at least one upper tool carrier assembly (150a, 150b) mounted on an upper tool carrier support portion (113) and at least one lower tool carrier assembly (150c, 150d) mounted on a lower tool carrier support portion (114), wherein the upper tool carrier assembly (150a, 150b) and the lower tool carrier assembly (150c, 150d) are configured to independently machine one or more workpieces (W) accommodated in the auxiliary spindle (131).

9. 9. The machine tool of claim 1, wherein the auxiliary spindle (131) includes one or more chucks with independently moving jaws for holding an irregularly shaped workpiece (W), the auxiliary spindle (131) includes two or more separate independent chucks spaced apart along the auxiliary spindle axis (XA), and / or the auxiliary spindle (131) includes a double-cone collet for clamping the workpiece (W).

10. The machine tool according to any one of claims 1 to 9, wherein the auxiliary spindle (131) is mounted on a tool carrier of an upper tool carrier support part (113) or a lower tool carrier support part (114) of the machine frame (110).

11. 6. The machine tool of claim 5, comprising: two upper tool carrier assemblies (150a, 150b) mounted on an upper tool carrier support portion (113) and two lower tool carrier assemblies (150c, 150d) mounted on a lower tool carrier support portion (114), each tool carrier assembly comprising a tool carrier, said tool carriers configured to independently machine workpieces (W) accommodated in said auxiliary spindle (131) and / or said main spindle (121), and said tool carriers synchronously machine said workpieces.

12. The machine tool according to any one of claims 1 to 11, wherein the auxiliary spindle (131) is configured as a turret unit (T) having a turret disk (H2) configured to be rotatable by a first drive means (D1) around a disk axis (X) that is a rotation axis of the turret disk (H2), and a second drive means (D2) for pivoting the turret head (H) around a turret axis (Y), and the second drive means (D2) is a motor having a rotor arranged radially outside a stator.

13. A machining method for machining a workpiece using a machine tool according to any one of claims 1 to 12, comprising the steps of: Fixing a workpiece (W) to the auxiliary spindle (131); machining said clamped workpiece (W) from at least one side; The machining method comprising:

14. 14. The machining method according to claim 13, wherein the machining method is a bar machining method and the workpiece (W) to be processed is loaded through the rear into the main spindle (121) and from the main spindle (121) onto the auxiliary spindle (131).

15. 14. Machining method according to claim 13, wherein the machining method is a chucking method, in which the workpiece (W) to be processed is fixed to the auxiliary spindle (131) and machined in parallel on two opposite sides.

16. 15. The machining method according to claim 14, wherein the machining method is configured to simultaneously machine at least two workpieces (W), at least one workpiece (W) being accommodated in the auxiliary spindle (131) and one workpiece (W) being accommodated in the main spindle (121).

Images