THERMOFORMMASCHINE

Description

AREA OF INVENTION

[0001] The invention relates to thermoforming machines and in particular to drive arrangements for thermoforming machines. TECHNICAL BACKGROUND

[0002] Thermoforming machines as such are already known. A thermoforming machine is a forming machine for a starting material, in particular a plastic film or plastic sheet made of a thermoplastic.

[0003] The production of shaped parts from the raw material by thermoforming can be carried out, for example, as follows: For shaping, a blank of the raw material is clamped using a so-called clamping frame. The raw material is then heated and thus brought into a thermoelastic or thermoplastic state. A mold moves into this blank and seals against, for example, a clamping plate. The shaping is achieved in particular by applying a vacuum to one side of the raw material, and the surrounding air pressure then presses the material onto the mold. Such machines are therefore also called vacuum forming machines.

[0004] In some examples, the forming process can be supported by mechanical pressure from the opposite side if the force of air pressure is insufficient for shaping.

[0005] The main elements of such exemplary conventional thermoforming machines are therefore a machine table for carrying and moving the mold, the aforementioned clamping frame, and an upper punch to support the forming process, with these three elements usually requiring the highest forces to operate a thermoforming machine.

[0006] Movements of the machine table, the clamping frame, and, if applicable, the upper die were—and often still are—executed using pneumatic cylinders. Since the forces required for all three elements can range from approximately 10 to 100 kN, pneumatic drives have proven their worth over many years.

[0007] However, conventional pneumatic drives in thermoforming machines require synchronization of the moving elements, i.e., different pneumatic cylinders, to achieve synchronous operation.

[0008] Recently, instead of pneumatic drives, three-phase servo motors and gearboxes are used in thermoforming machines to reduce the relatively high motor speed and increase the torque. This drive acts on a ball screw or a rack and pinion. Since the assemblies such as the machine table, clamping frame, and, if applicable, the upper die often have a substantially rectangular shape, it has already been described how to install such a drive at each of the four corners. Consequently, a thermoforming machine today can, for example, have four drives for the clamping frame and four for the machine table, each at its corner. In the case of the upper die, two drives, or possibly four, are usually sufficient.

[0009] EP 2 944 451 A1, for example, describes a closed-chamber thermoforming machine in which a table for a mold and a clamping frame are each moved by means of spindle drives. The drive is provided by three-phase motors, each with a horizontally oriented axis of rotation. The three-phase motors are each coupled to a bevel gearbox and each drives a ball screw.

[0010] With this type of drive concept for movable machine components such as the table or the clamping frame, high traverse speeds as well as high precision and reproducibility in the positioning of these machine components can be achieved. At the same time, this drive concept makes it possible to avoid mechanical synchronization, which, for example, requires lubrication, involves maintenance, and is subject to wear. Synchronization of several individual drives can be achieved electronically via the control system.

[0011] Although such drives based on three-phase motors are very advantageous for thermoforming machines, it has been found that the angle gearboxes used incur considerable costs. Three-phase servo motor drives with gearboxes can be significantly more expensive than conventional pneumatic drives. Reducing the number of expensive three-phase servo motors with gearboxes, for example by using fewer drives per machine component to be moved, may in turn necessitate mechanical synchronization.

[0012] Furthermore, while such bevel gears, for example, are durable and reliable, they still require a certain amount of care, maintenance, and / or lubrication, due to factors such as the rolling teeth. Additionally, the operation of gear drives, in particular, generates noise.

[0013] The machine described in EP 2 944 451 A1 is already very advantageous in terms of space utilization and compact design. Nevertheless, sufficient installation space must be provided for the bevel gearboxes.

[0014] Furthermore, DE 10 2009 045 543 B4 describes a drive unit for a forming and / or stamping machine for generating a linear vertical relative movement between two tool tables. One or more drive motors and a coupling unit for converting a rotational movement of the drive motor(s) into a linear movement are described, wherein the coupling unit comprises a spindle drive and a toggle lever system.

[0015] In JP 2010 284 862 A, a press molding machine for forming a plastic sheet is also described, which has four electromechanical cylinders and a control system for them.

[0016] Therefore, it would be desirable to further reduce the costs for driving the movable machine components of a thermoforming machine and preferably also to further reduce wear and tear as well as maintenance and upkeep requirements. Furthermore, it would be particularly desirable if the space required for drive units and / or their noise emissions could be reduced even further. SUMMARY OF THE INVENTION

[0017] Against this background, the object of the present invention is to create a thermoforming machine that is cost-effective in terms of manufacture and / or maintenance, as well as being more compact and, in particular, operating with less noise.

[0018] This problem can be solved with a thermoforming machine having the features of claim 1 and / or with a thermoforming machine having the features of claim 3 and / or with a thermoforming machine having the features of claim 10 and / or with a thermoforming machine having the features of claim 14.

[0019] Accordingly, a thermoforming machine is proposed according to the invention, which has: The system comprises at least one translationally movable machine component by means of which a force can be applied to the starting material during thermoforming for the production of a molded part, and at least one electric machine for driving the machine component for its translational movement. The electric machine is designed as a rotary electric machine, and to generate movement for the translational movement of the machine component, a rotatable rotor of the electric machine is directly coupled to an element of a spindle drive.

[0020] Furthermore, the translationally movable machine component is designed as a movable machine table for a mold. The rotating electric machine is arranged on a lateral extension of a supporting part of the machine table, extending transversely to the direction of travel of the machine table, between a clamping plane for the starting material and a plane defined by a lower edge of the supporting part of the machine table.

[0021] This allows the mold to be moved with reduced costs and space requirements, as well as reliably, quickly, quietly, with minimal maintenance, and with high precision. Furthermore, a space-saving arrangement of the electric motor is enabled, especially since a certain amount of installation space is required in the direction of travel for the machine table and its supporting component to provide a sufficiently strong machine table capable of supporting the weight of the mold and the forming forces. Preferably, the rotating electric motor is located in an upper travel position of the machine table, intended for operation of the thermoforming machine, between the plane defined by the lower edge and the clamping plane.

[0022] According to the invention, a thermoforming machine is further proposed which has: The system comprises at least one translationally movable machine component by means of which a force can be applied to the starting material during thermoforming for the production of a molded part, and at least one electric machine for driving the machine component for its translational movement. The electric machine is designed as a rotary electric machine, and to generate movement for the translational movement of the machine component, a rotatable rotor of the electric machine is directly coupled to an element of a spindle drive.

[0023] Furthermore, the translationally movable machine component is designed as a movable machine table for a forming tool. The rotating electric machine is rigidly coupled to a machine housing of the thermoforming machine and is arranged between a clamping plane for the starting material and a plane defined by the lower edge of a supporting part of the machine table.

[0024] Thus, the forming tool can be moved with reduced costs and space requirements, as well as reliably, quickly, quietly, with minimal maintenance, and with high precision. Such a design according to the invention can, for example, contribute to reducing the moving masses and the number of supply lines, such as electrical cables, to moving components. In this case, the rotating electric motor can be located, particularly in an upper travel position of the machine table intended for operation of the thermoforming machine, between the plane defined by the lower edge and the clamping plane.

[0025] Furthermore, the invention proposes a thermoforming machine which has: The system comprises at least one machine component capable of translational movement, by means of which a force can be applied to the starting material during thermoforming to produce a molded part, and at least one electric machine for driving the machine component for its translational movement. The electric machine is designed as a linear motor, and a translationally movable rotor of the linear motor is directly coupled to the machine component.

[0026] Furthermore, the translationally movable machine component is designed as a movable machine table for a mold. The rotor of the linear motor is rigidly connected to a supporting part of the machine table and is arranged between a clamping plane for the starting material and a plane defined by a lower edge of the supporting part of the machine table.

[0027] Thus, the forming tool can be moved with reduced costs and space requirements, as well as reliably, quickly, quietly, with minimal maintenance, and with high precision. This design according to the invention also contributes to a space-saving construction. Here, the runner can preferably be located, particularly in an upper travel position of the machine table intended for operation of the thermoforming machine, between the plane defined by the lower edge and the clamping plane.

[0028] One of the underlying ideas of the invention is that, by means of the direct mechanical coupling of the rotatable rotor with an element of the spindle drive or the use of a linear motor and the direct mechanical coupling of the translatable rotor of the same with the machine component, a mechanical speed conversion between two rotary movements, such as by means of a bevel gear drive, can be avoided.

[0029] This design requires less space and allows for more compact installation of the drive unit. Furthermore, eliminating the mechanical transmission, such as the bevel gear, reduces costs. Additionally, it eliminates the noise generated by components like bevel gears, which results from the grinding action of the meshing teeth.

[0030] Furthermore, by avoiding the angle gear, the maintenance and care effort for the drive can be reduced, resulting in significantly reduced maintenance costs and significantly reduced wear.

[0031] The invention thus advantageously enables the elimination of costly mechanical transmissions and, by reducing or eliminating the effort required for the mechanical conversion of the drive motion, contributes to a simplified design and space savings, thereby allowing the thermoforming machine to be built more cost-effectively and compactly. Furthermore, reducing the number of moving mechanical components can help to decrease maintenance and lubrication costs as well as wear and tear, and to achieve high reliability. Given the considerable number of, for example, ten individual drives in a thermoforming machine, the aforementioned savings and improvements can have an even greater impact on the overall machine.

[0032] The linear motor also enables the direct provision of translational movement without mechanical elements to convert a rotary movement into a translational movement.

[0033] Advantageous embodiments and further developments of the invention will result from the dependent claims and from the description with reference to the figures of the drawing.

[0034] By designing the movable machine component as a clamping frame for clamping the starting material for its forming, a reliable, fast and precise clamping frame process is achieved with reduced effort, lower costs, reduced installation space requirements and low noise generation.

[0035] If the movable machine component is designed as a forming aid, particularly as an upper die, it can be moved precisely, quickly, reliably, and quietly, thereby reducing costs and the required installation space. While the forming aid, such as the upper die, may be useful in some forming processes, it can be deactivated for the production of other molded parts, or the thermoforming machine can be designed without the forming aid, such as the upper die, in other configurations.

[0036] In a preferred embodiment, the rotating electric machine is designed as a three-phase servomotor, in particular a torque motor. Such an electric motor is designed and suitable to provide a comparatively very high torque without the use of a gearbox.

[0037] In one embodiment, the rotating electric machine is arranged on the translationally movable machine component in such a way that the electric machine moves along with the machine component in the direction of travel. Such a moving electric machine can be useful, for example, if suitable installation space for a moving electric machine is available or can be easily provided, given the installation conditions in the thermoforming machine.

[0038] In another embodiment, a stator of the rotating electric machine can be rigidly coupled to a machine housing.

[0039] According to a further development, a spindle or nut of the spindle drive can be driven directly by means of a rotating electric machine as the driven element to generate the motion for the translational operation of the machine component, in particular without the need for an intermediate gearbox between the rotor of the rotating electric machine and the driven element. Specifically, the rotational speed of the rotor of the rotating electric machine during operation corresponds to the rotational speed of the driven element of the spindle drive. Such a spindle drive enables reliable movement of the machine component, thereby avoiding the need for an additional gearbox, and simultaneously maintaining a mechanical connection in the vertical direction through the engagement of the nut and spindle.

[0040] In a further embodiment, the rotating electric machine has a hollow shaft, with the driven element being non-rotatably connected to the hollow shaft. In particular, the spindle of the spindle drive can extend axially through an inner region of the hollow shaft. For example, the nut can be arranged in or on the hollow shaft, and / or a section of the spindle can be located inside the hollow shaft. This allows for a direct and space-saving drive of the driven element.

[0041] In particular, the nut, the spindle and the hollow shaft are arranged concentrically to each other.

[0042] According to a further development, the rotating electric machine can be designed as a three-phase servomotor that directly incorporates an integrated nut for the spindle drive, thus driving the nut without a gear. Such a three-phase servomotor can help simplify the assembly of the thermoforming machine and saves space.

[0043] In one embodiment, the translationally movable machine component can be moved along a substantially vertical direction during operation of the thermoforming machine. This improves the drive system for machine components that move vertically during thermoforming. In particular, the translationally movable machine component can move in a straight line. Such movement is advantageously relatively easy to implement.

[0044] According to one refinement, the axis of rotation of the rotating electric machine is arranged essentially vertically. In another refinement, the linear motor has an essentially vertical direction of movement. This allows for a further simplification of the thermoforming machine's design.

[0045] According to further training, the thermoforming machine is designed as a closed-chamber thermoforming machine and / or as a single-station thermoforming machine. This will make it possible to provide an improved drive concept for thermoforming machines that enable a variety of forming processes in a compact manner and with a small footprint. CONTENT OF THE DRAWING

[0046] The invention will now be explained in more detail with reference to the exemplary embodiments shown in the schematic figures. These figures show... Fig. 1 a thermoforming machine in front view, with schematically sketched machine components and drive arrangements according to exemplary embodiments of the invention; Fig. 2 the thermoforming machine of the Fig. 1 in top view, whereby an upper die and drive arrangements for it are not shown; Fig. 3 a schematic front view of a part of the thermoforming machine of the Fig. 1 with an additionally shown upper die of the same and schematically sketched drive devices for the upper die; Fig. 4 a drive arrangement for driving a machine table of the thermoforming machine of the Fig. 1 , in a section view A - A, see Fig. 2 , according to a first embodiment; Fig. 5 a drive arrangement for driving a clamping frame of the thermoforming machine of the Fig. 1 , in a section C - C, see Fig. 2 , according to a second embodiment; Fig. 6 a drive arrangement for driving the upper die of the thermoforming machine of the Fig. 1 in a section view B-B, see Fig. 2 , according to a third embodiment; Fig. 7 a drive arrangement for driving the machine table of the thermoforming machine of the Fig. 1 according to a fourth embodiment, in which section A - A as in Fig. 2 sketched; Fig. 8 a drive arrangement for driving the clamping frame of the thermoforming machine of the Fig. 1 according to a fifth embodiment, in a section C - C as in Fig. 2 sketched; Fig. 9 a drive arrangement for driving the machine table of the thermoforming machine of the Fig. 1 according to a sixth embodiment, in which section A - A as in Fig. 2 sketched; Fig. 10 a drive arrangement for driving the upper die of the thermoforming machine of the Fig. 1 in the B-B section as in Fig. 2 sketched, according to a seventh embodiment; and Fig. 11 a drive arrangement for driving the clamping frame of the thermoforming machine of the Fig. 1 according to an eighth embodiment, in a section C - C as in Fig. 2 hinted at.

[0047] The accompanying drawings are intended to provide a further understanding of the embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain the principles and concepts of the invention. Other embodiments and many of the advantages mentioned will become apparent with reference to the drawings.

[0048] In the figures of the drawing, identical, functionally equivalent, and similarly acting elements, features, and components are—unless otherwise stated—each identified by the same reference symbols. The elements of the drawings are not necessarily drawn to scale. DESCRIPTION OF EXAMPLES OF EXECUTION

[0049] In Fig. 1-3 A single-station thermoforming machine 1 is schematically sketched with several translationally movable machine components 2, 3, and 4, and drive arrangements 6, 7, and 8 for these. The thermoforming machine 1 is set up for operation on a base extending essentially in a horizontal direction H. The machine components 2, 3, and 4 are translationally movable essentially parallel to a vertical direction V. Translational vertical movements 17 of components 2 and 3 are shown in Fig. 1 Illustrated by example.

[0050] Fig. 1 Figure 5 further shows a machine housing 5 with a lower box-like closed part and an upper frame-like area, and with a horizontal machine plate 10 arranged on the upper side of the box-like closed part of the machine housing 5. Through the machine plate 10 or a window plate sealing against it, in Fig. 1 Not shown, a substantially horizontal clamping plane 13 is defined for a starting material 9. The starting material 9 is provided in particular as a plastic film or sheet made of a thermoplastic material.

[0051] Thermoforming machine 1 is designed as a closed-chamber thermoforming machine, wherein the in Fig. 1 The lower, box-like part of the machine housing 5 is closed and sealed during operation. In this way, the air pressure in the closed part of the machine housing 5 below the machine plate 10 can be controlled, and the closed part can be pressurized in particular to prevent the starting material 9 from sagging after heating.

[0052] A first machine component is designed as a movable machine table 2. The machine table 2 carries a Fig. 1 The forming tool is not shown. A vertical movement of the tool is achieved by means of the machine table 2. The machine table 2 is vertically movable below the clamping plane 13.

[0053] During the thermoforming process, the forming tool is moved from below into the heated plastic film or sheet 9. This movement is achieved by means of the drive arrangements 6 for the table 2 with a force sufficient to lift the weight of the forming tool and press it into the often viscous, heated plastic film or sheet 9. The lifted forming tool is then pressed against the clamping system described below to create a seal. The forces applied range, for example, from approximately 10 kN to approximately 100 kN.

[0054] A second machine component of the thermoforming machine 1 is designed as a clamping frame 3. The clamping frame 3 is movable above the clamping plane 13 parallel to the vertical direction V. The drive arrangements 7 for the clamping frame 3 are configured to move the weight of the clamping frame up and down and to press the plastic film or sheet 9 against the seal on the machine plate 10. The forces applied range, for example, from approximately 10 kN to approximately 100 kN.

[0055] A third machine component of the thermoforming machine 1 is designed as a forming aid in the form of an upper die 4, see also Fig. 3 The upper die 4 assists the forming process through the application of mechanical force using a suitable printing or embossing tool. The forces applied are similar to those used for machine table 2 and clamping frame 3.

[0056] Therefore, the following translational component movements are provided for the operation of thermoforming machine 1: a movement 17 of the clamping frame 3 for clamping the material 9 and further for later releasing the formed part; a movement 17 of the machine table 2 with the form carried by it into the material blank 9 and out again for demolding; a movement 17 of a forming aid, in particular the upper punch 4, to support the forming, in addition to the forces acting due to the air pressure.

[0057] The following are therefore planned in Fig. 1 For example, four drive arrangements 6 for the machine table 2 in the area of ​​the four corners of the essentially rectangular machine table 2, four drive arrangements 7 for the clamping frame 3 in the area of ​​the four corners of the essentially rectangular clamping frame 3, and two drive arrangements 8 for the upper die 4, see also Fig. 3 In Fig. 1 The drive arrangements 7 are shown schematically with dashes, and the drive arrangements 6 with double dashes. The position of the drive arrangements 8 overall is shown. Fig. 1 schematically in dotted line, Fig. 3 Figure 8 schematically shows the positions of the individual drive arrangements in double-dash lines. A total of ten drives are thus provided for the three elements 2, 3, and 4. The clamping forces of 10 kN to 100 kN are distributed among the (for example, two or four) drives of each element, i.e., table 2, clamping frame 3, or upper punch 4.

[0058] The following describes exemplary embodiments of the invention that implement a gearless drive concept for the individual drives of the thermoforming machine 1 described above. Preferably, a plurality of identically designed drive arrangements can be used to drive each of the components 2, 3, or 4, whereby the type of drive arrangements may differ, for example, from machine component to machine component. Furthermore, in variants of the exemplary embodiments, other numbers of drive arrangements than those specified above for each component 2, 3, or 4 are conceivable. For example, in one variant for the upper die 4, four drive arrangements 8 are conceivable.

[0059] Fig. 4 Section AA shows a drive arrangement 6 for the machine table 2. Only a part of the machine table 2 is shown in Fig. 4 A supporting part 11 of the machine table 2 in the form of a supporting substructure has a lateral extension 12, which projects laterally beyond a table top 2a of the table 2 which supports the tool and extends transversely to the direction of travel 17 and thus transversely to the vertical V and essentially in the horizontal direction H.

[0060] A rotating electric machine 20, designed as a three-phase servomotor and specifically as a torque motor, is attached to the top of the extension 12. In this way, the torque motor 20 is arranged in a space-saving manner between the clamping plane 13 for the input material 9 and a substantially horizontal plane 15 defined by a lower edge 14 of the supporting part 11.

[0061] In the exemplary embodiment of the Fig. 4 The torque motor 20 is moved along with the machine table 2 in the direction of travel 17 during the vertical translational movement of the machine table 2.

[0062] The torque motor 20 has a stator 22 and a rotor 21 rotatably arranged within the stator 22. The stator 22 is rigidly coupled to the supporting part 11 in the region of the extension 12. An axis of rotation 16 of the rotor 21 is substantially parallel to the vertical direction V. The rotor 21 is formed with a hollow shaft 23. A nut 26, in particular a ball screw nut, is received in the hollow shaft 23 of the torque motor 20 and non-rotatably connected to the hollow shaft 23. The nut 26 engages with a spindle 25, in particular a ball screw, which is fixed both axially and circumferentially. The rotor 21, the hollow shaft 23, the nut 26, and the spindle 25 are arranged coaxially with each other and with the axis of rotation 16. The spindle 25 extends axially through the nut 26 and an interior of the hollow shaft 23.

[0063] The nut 26 and the spindle 25 form a spindle drive 24, whereby the nut 26 can be directly driven by the torque motor 20 to move the machine table 2 translationally. No gearbox is interposed between the nut 26 and the rotor 21; the drive is gearless in this sense. The rotational speed of the rotating rotor 21 corresponds to the rotational speed of the nut 26.

[0064] To achieve a suitable ratio between the rotational speed of the torque motor 20 and the speed of the translational process 17 of the table 2, thereby realizing a gear ratio and providing the desired forces, the pitch of the spindle 25 and the power of the torque motor 20 are appropriately selected. Even if the power output is increased compared to conventionally installed three-phase motors, this is in Fig. 4 The illustrated embodiment is advantageous because no expensive gearbox is needed between the nut 26 and the hollow shaft 23.

[0065] A drive arrangement 7 for the clamping frame 3 according to an exemplary embodiment is shown. Fig. 5 , wherein the drive arrangement 7 is analogous to that of the Fig. 4 is structured. In Fig. 5 A spindle drive 24 with a spindle 25 fixed axially and circumferentially is also provided, the spindle 25 projecting substantially vertically upwards from the machine plate 10. Thus, an electric motor 20 is provided at each corner of the clamping frame 3, the stator 22 of which is rigidly coupled to the clamping frame 3. The hollow shaft 23 of the rotor 21 receives the nut 26 in a rotationally fixed manner. By rotating the rotor 21 of each of the torque motors 20 about its substantially vertical axis of rotation 16, the clamping frame 3 can be moved in a substantially vertical direction V, as indicated by reference numeral 17.

[0066] In drive arrangements 6 and 7 of the Fig. 4 , 5 To effect the movements of the machine table 2 or the clamping frame 3 of the thermoforming machine 1, the electric machine 20 is installed in such a way that it moves along with the moving component 2 or 3. The driven nut 26 runs up and down on a statically arranged, rigidly clamped spindle 25.

[0067] Fig. 6 Figure 8 shows a drive arrangement 8 for the upper die 4 according to a further embodiment in a section plane BB. Here, a torque motor 20 is provided with a stator 22 and a rotor 21 with a hollow shaft 23, wherein the stator 22 is rigidly coupled to the machine housing 5, and in the illustrated embodiment, to a part 5a of the machine housing 5 extending transversely above a working area of ​​the thermoforming machine 1. A nut 26", in particular a ball screw nut, is arranged in the hollow shaft 23, non-rotatably connected to the hollow shaft 23, and thus directly driven by means of the rotor 21. A spindle 25", in particular a ball screw, extends axially through the nut 26" and the hollow shaft 23, coaxially to the nut 26", the rotor 21, the hollow shaft 23, and the axis of rotation 16. The nut 26" and the spindle 25" engaged with it form a spindle drive 24" for driving the upper punch 4.The spindle 25" is fixed in the circumferential direction, so it is not rotated when the upper punch 4 is moved, but it is displaceable along the axis 16 parallel to the vertical direction V. A rotation of the nut 26" causes the axial displacement of the spindle 25" and thus the translational movement 17 of the upper punch 4 connected to the spindle 25". This also applies in the case of... Fig. 6 The pitch of the spindle (25") and the motor power of the torque motor (20) can be appropriately adjusted.

[0068] A drive arrangement 106 for the machine table 2 according to a further embodiment shows Fig. 7 The arrangement 106 can be used in machine 1 of the Fig. 1, 2 instead of arrangement 6, to move the table 2 translationally in the vertical direction V.

[0069] The drive arrangement 106 comprises a rotating electric machine 20 designed as a torque motor, the stator 22 of which is rigidly coupled to the machine housing 5. The torque motor 20 is arranged below the machine plate 10 and is located in all operating positions of the machine table 2, including its uppermost position, between the clamping plane 13 and the plane 15 defined by the lower edge 14 of the supporting part 11.

[0070] A rotatable rotor 21 of the torque motor 20 has a hollow shaft 23 through which a Fig. 7 A spindle 25' extends axially and concentrically to the rotor 21 with the hollow shaft 23 and to a substantially vertical axis of rotation 16 of the rotor 21. The spindle 25' can be supported at its upper end in the machine housing 5, as shown in Fig. 7 The upper bearing can be shown graphically, or it can be part of the electric machine 20. The spindle 25' is thus rotatable about the axis 16 and at the same time fixed in the axial direction 16, wherein the spindle 25' is connected to the hollow shaft 23 in a rotationally fixed manner and can be driven directly by the electric machine 20.

[0071] The spindle 25', for example a ball screw, together with a nut 26', which is in particular designed as a ball screw nut, forms a spindle drive 24' by means of which the table 2 can be driven for movement in the direction of travel 17. The nut 26' is connected to the extension 12 of the supporting part 11 in a rotationally fixed and axially fixed manner and runs up and down on the rotating spindle 25' when the motor 20 is in operation.

[0072] Thus, in Fig. 7 The rotatable rotor 21 is directly coupled to the spindle 25' as an element of the spindle drive 24' without the interposition of a gearbox; the rotational speed of the spindle 25' corresponds to the rotational speed of the rotor 21.

[0073] In Fig. 8 A drive arrangement 107 for the clamping frame 3 is shown according to a further embodiment, wherein the drive arrangement 107 is in Fig. 1 can be used instead of the drive arrangement 7.

[0074] The drive arrangement 107 comprises a torque motor 20 as a rotating electric machine 20. It is a spindle drive 24' with a spindle 25' and a Fig. 8 mother 26' not shown in detail, which is analogous Fig. 7 is trained.

[0075] In this embodiment, the spindle 25' protrudes Fig. 8 essentially vertically upwards from the machine plate 10 of the thermoforming machine 1 and is rotatable about an essentially vertical axis of rotation 16, but axially fixed.

[0076] The spindle 25' is non-rotatably connected in the region of its lower end to a hollow shaft 23 of a rotatable rotor 21 of the torque motor 20, the spindle 25' extending axially in sections through a hollow interior of the hollow shaft 23. Fig. 8 The spindle 25', the rotor 21 with the hollow shaft 23, and the axis 16 are arranged coaxially to each other. A stator 22 of the electric machine 20 is rigidly coupled to the machine housing 5.

[0077] If the spindle 25', in particular a ball screw, is rotated by means of the electric machine 20, then the in Fig. 8 The nut 26', in particular a ball screw nut, which is not shown and is connected to the clamping frame 3 in the axial and circumferential directions, and thus fixed against displacement and rotation, is moved along the spindle 25'. By operating the torque motors 20 to rotate the spindles 25' in the area of ​​the four corners of the clamping frame 3, the clamping frame 3 can be moved in the vertical direction V. Also in Fig. 8 The runner 21 is directly coupled to the spindle 25' without the use of an intermediate gearbox.

[0078] In Orders 106 and 107 of the Fig. 7 and 8The electric machine 20 is thus statically installed in the thermoforming machine 1, and the spindle 25', which is preferably designed as a ball screw, is rotated. The nut 26', preferably also a ball screw nut, then runs up and down on the spindle 25', and together with other nuts 26', it supports the table 2 or the clamping frame 3. An analogous embodiment, in which, for example, two nuts 26' support the upper die and run up and down on rotatable, axially fixed spindles 25', is also conceivable.

[0079] A drive arrangement 206 for the machine table 2 of the thermoforming machine 1 according to yet another embodiment of the invention is shown schematically. Fig. 9 On average AA. Arrangement 206 can be used instead of arrangement 6 of the Fig. 1 to be used.

[0080] In the drive arrangement 206, an electric machine is provided for driving the table 2 for its translational movement; this machine is designed as a linear motor 60. A rotor 61 of the linear motor 60, which is movable translationally essentially along the vertical direction V, is directly coupled to the machine component 2, which is designed as a machine table, and is rigidly connected to the lateral extension 12 of the supporting part 11 of the machine table 2. A stationary stator 62 of the linear motor 60 extends along the vertical direction V below the machine plate 10 within the interior of the machine housing 5, and the stator 62 is fixed to the machine housing 5. The stator 62 can also be referred to as the travel path of the linear motor 60. Fig. 9 The figure also shows that the runner 61 is arranged between the clamping plane 13 for the starting material 9 and the plane 15 defined by the lower edge 14 of the supporting part 11, for each travel position of the table 2 intended for operation of the thermoforming machine. By operating the linear motors 60 at the four corners of the machine table 2, it can be moved translationally up and down along the vertical V, as indicated by reference numeral 17. The arrangement 206 thus manages with a further reduced number of moving parts; vertically, the table 2 is held and moved "floating" by means of the linear motors 60.

[0081] Preferably in the exemplary embodiment the Fig. 9 A linear guide (not shown) is provided for the lateral guidance of the machine table 2 during the vertical movement 17, which can be designed, for example, as a sliding guide or using rolling elements. Furthermore, in the exemplary embodiment, the Fig. 9 To further improve safety and reliability, a braking device should be provided which prevents the machine component 2, designed as a machine table, from falling, for example in the event of a power failure. The braking device is located in Fig. 9 Not shown in detail for the sake of clarity.

[0082] Fig. 10 schematically shows a drive arrangement 208 for the upper die 4, which is implemented with an electric machine 60 designed as a linear motor 60 and replaces the arrangement 8 in Fig. 1 can be used. Here, a stand 62' of the linear motor 60 is arranged on the machine housing 5, specifically on the part 5a of the machine housing 5 that extends horizontally transversely above the machine plate 10 and the clamping plane 13, and is rigidly coupled to the part 5a. The stand 62' of the linear motor 60 in Fig. 10 can in particular the translationally movable runner 61 of the linear motor 60 Fig. 9 are equivalent to.

[0083] A rotor 61' of the linear motor 60 is arranged to be axially displaceable in the vertical direction V relative to the machine housing 5 and is mounted on a Fig. 10 The lower end of the runner 61' is firmly connected to the upper die 4. The translationally movable runner 61' of the Fig. 10 can the stator 62 of the Fig. 9 be appropriately trained.

[0084] When operating the linear motors 60 of the two exemplary drive arrangements 208 for the upper punch 4, the latter can be moved quickly and precisely translationally in the direction of travel 17, essentially parallel to the vertical V. Alternatively, for example, four drive arrangements 208 for the upper punch 4 are conceivable for implementing this movement.

[0085] A drive arrangement 207 for the clamping frame 3 according to a further embodiment shows Fig. 11 in a schematic manner. Arrangement 207 can be in Fig. 1 to be used instead of arrangement 7.

[0086] This is analogous Fig. 9 a stand 62 extending along the vertical direction V is provided, which is connected to the Fig. 11 The machine housing 5 (not shown) is fixedly and immovably connected to the clamping frame 3. A rotor 61 of the linear motor 60 is fixedly connected to the clamping frame 3.

[0087] Also in the case of orders 207 and 208 of the Fig. 11 In each case 10 a braking device, not shown in detail in the figures, is provided to prevent the clamping frame 3 or the upper punch 4 from falling uncontrollably in the event of a power failure.

[0088] Fig. 4-8 Illustrate exemplary embodiments in which a drive concept for a thermoforming machine 1 is implemented, which makes use of electric motors with very high torque, so-called torque motors.

[0089] The torque motors 20, each with either the integrated ball screw nut 26, 26" or the directly driven spindle 25', for example, installed in the area of ​​each of the four corners of the clamping frame 3 or the table 2, or for example in the area of ​​two sides of the upper die 4, can thus move the components 2, 3, 4 without the need for a gear drive to convert speed and torque. The power of the torque motors 20, the achievable torque, and the pitch of the spindle 25, 25', 25" are preferably selected such that the desired traverse speeds and the forces to be applied by the components 2, 3, 4 for forming the material 9 can be achieved with the desired reliability and, if necessary, a safety margin. For example, the power of the torque motor 20 can be increased and the pitch of the spindle 25, 25', 25" decreased to achieve the desired speeds and forces.

[0090] Fig. 9-11 Figure 1 shows exemplary embodiments in which linear motors 60 operating vertically V are provided. A substantially vertical direction of movement of the linear motor 60 is shown in Figure 2. Fig. 9-11 Designated with reference numeral 18.

[0091] In this case, a vertical linear guide is provided, for example, with a first effective part as stator 62, 62', and the component to be moved - for example the table 2, the clamping frame 3 or the upper punch 4 - with a second effective part as runner 61, 61' of the linear motor 60.

[0092] In the embodiments described above, four drive arrangements 6, 106 or 206 are preferably provided for the machine table 2, and four drive arrangements 7, 107 or 207 for the clamping frame 3. For the upper punch 4, for example, two drive arrangements 8 or 208 can be provided. An upper punch 4 with four drive arrangements 8 or 208, each arranged in the region of one of the four corners of the upper punch 4, is also conceivable.

[0093] Synchronization of the traversing motion 17 of the several individual drive arrangements of each component 2, 3, 4 can be achieved by means of electronic control without the need for mechanical synchronization. List of reference symbols

[0094] 1 Thermoforming machine 2 Machine table 2a Table top 3 Clamping frame 4 Upper punch 5 Machine housing 5a Transverse part (machine housing) 6 Drive arrangement (for machine table) 106 Drive arrangement (for machine table) 206 Drive arrangement (for machine table) 7 Drive arrangement (for clamping frame) 107 Drive arrangement (for clamping frame) 207 Drive arrangement (for clamping frame) 8 Drive arrangement (for upper punch) 208 Drive arrangement (for upper punch) 9 Starting material 10 Machine plate (machine housing) 11 Supporting part (machine table) 12 Extension (supporting part) 13 Clamping plane 14 Lower edge 15 Plane 16 Axis of rotation (rotating electric machine) 17 Direction of travel 18 Direction of movement (linear motor) 20 Rotating electric machine 21 Rotor (rotating electric machine) 22 Stand (rotating electric machine) 23 Hollow shaft 24 Spindle drive 24' Spindle drive 25 Fixed spindle 25' Rotating spindle 26 Rotating traveling nut 26' Circumferentially fixed,Moving nut 24" Spindle drive 25" Circumferentially fixed, movable spindle 26" Rotating nut 60 Linear motor 61 Rotor (Linear motor) 61' Rotor (Linear motor) 62 Stand (Linear motor) 62' Stand (Linear motor) Horizontal direction Vertical direction

Claims

1. Thermoforming machine (1) comprising at least one translationally movable machine component (2), by means of which a force can be applied to a starting material (9) during the thermoforming of the starting material (9) for the production of a moulded part, and at least one electric machine (20) for driving the machine component (2) for the translational movement thereof; wherein the electric machine (20) is designed as a rotating electric machine and a rotatable rotor (21) of the electric machine (20) is directly coupled to an element (26) of a spindle drive (24) in order to generate a movement for the translational movement of the machine component (2); wherein the translationally movable machine component (2) is designed as a movable machine table (2) for a moulding tool; and wherein the rotating electric machine (20) is arranged on a lateral extension (12), which extends transversely to the direction of movement (17) of the machine table (2), of a supporting part (11) of the machine table (2) between a clamping plane (13) for the starting material (9) and a plane (15) that is defined by a lower edge (14) of the supporting part (11) of the machine table (2).

2. Thermoforming machine according to claim 1, characterised in that the rotating electric machine (20) is arranged on the translationally movable machine component (2) in such a manner that the electric machine (20) is moved along with the machine component in the direction of movement (17) during the movement thereof.

3. Thermoforming machine (1) comprising at least one translationally movable machine component (2), by means of which a force can be applied to a starting material (9) during the thermoforming of the starting material (9) for the production of a moulded part, and at least one electric machine (20) for driving the machine component (2) for the translational movement thereof; wherein the electric machine (20) is designed as a rotating electric machine and a rotatable rotor (21) of the electric machine (20) is directly coupled to an element (25') of a spindle drive (24') in order to generate a movement for the translational movement of the machine component (2); wherein the translationally movable machine component (2) is designed as a movable machine table (2) for a moulding tool; and wherein the rotating electric machine (20) is fixedly coupled to a machine housing (5) of the thermoforming machine (1) and in this case is arranged between a clamping plane (13) for the starting material (9) and a plane (15) that is defined by a lower edge (14) of the supporting part (11) of a machine table (2).

4. Thermoforming machine according to claim 3, characterised in that a stator (22) of the rotating electric machine (20) is fixedly coupled to a machine housing (5).

5. Thermoforming machine according to one of the preceding claims, characterised in that the rotating electric machine (20) is designed as a three-phase servomotor, in particular a torque motor.

6. Thermoforming machine according to one of the preceding claims, characterised in that a spindle (25') or a nut (26) of the spindle drive (24; 24') for generating the movement for the translational movement of the machine component (2) can be driven directly, in particular without the interposition of a gear between the rotor (21) of the rotating electric machine (20) and the driven element (26; 25'), and in particular that a speed of the rotor (21) of the rotating electric machine (20) during operation thereof corresponds to a speed of the driven element (26; 25') of the spindle drive (24; 24').

7. Thermoforming machine according to claim 6, characterised in that the rotating electric machine (20) comprises a hollow shaft (23), wherein the driven element (26; 25') is connected to the hollow shaft (23) in a rotationally fixed manner and in particular wherein the spindle (25; 25') of the spindle drive (24; 24') extends axially through an inner region of the hollow shaft (23).

8. Thermoforming machine according to one of the preceding claims, characterised in that the translationally movable machine component (2) is movable along an essentially vertical direction (V) during operation of the thermoforming machine (1).

9. Thermoforming machine according to one of the preceding claims, characterised in that an axis of rotation (16) of the rotating electric machine (20) is arranged essentially vertically.

10. Thermoforming machine (1) comprising at least one translationally movable machine component (2), by means of which a force can be applied to a starting material (9) during the thermoforming of the starting material (9) for the production of a moulded part, and at least one electric machine (60) for driving the machine component (2) for the translational movement thereof; wherein the electric machine (60) is designed as a linear motor and a translationally movable rotor (61) of the linear motor (60) is directly coupled to the machine component (2); wherein the translationally movable machine component (2) is designed as a movable machine table (2) for a moulding tool; and wherein the rotor (61) of the linear motor (60) is fixedly connected to a supporting part (11) of the machine table (2) and is arranged between a clamping plane (13) for the starting material (9) and a plane (15) that is defined by a lower edge (14) of the supporting part (11) of the machine table (2).

11. Thermoforming machine according to claim 10, characterised in that the translationally movable machine component (2) is movable along an essentially vertical direction (V) during operation of the thermoforming machine (1).

12. Thermoforming machine according to claim 10 or 11, characterised in that the linear motor (60) comprises an essentially vertical direction of movement (18).

13. Thermoforming machine according to one of the preceding claims, characterised in that the thermoforming machine (1) is designed as a closed-chamber thermoforming machine and / or in that the thermoforming machine (1) is designed as a single-station thermoforming machine.