Multi-part clamp unit and stretching apparatus

Abstract

The present invention relates to a multi-piece clamping unit (28) for a stretching device (10), the clamping unit having a main component (32) and at least two guides (34). The main component has a base (36) and a clamping device (30) for clamping a material web (12), and each guide has a base (42) and at least one guide element (44) for guiding on a track (17) of the stretching device. The bases of the guides and the bases of the main component are manufactured as separate components and fixed to each other, the bases of each guide and the base of the main component are made of metal and manufactured by casting, the clamping unit has a main direction, and the bases of each guide are fixed to the main component by means of a threaded part of the clamping unit extending parallel to the main direction. Furthermore, the present invention also relates to a stretching device.

Description

Technical Field

[0001] This invention relates to a multi-piece clamp unit and a stretching device having a multi-piece clamp unit. Background Technology

[0002] Stretching equipment is particularly used for manufacturing plastic films. Typically, in such equipment, a web of material to be stretched, usually a plastic film, is gripped and moved through the equipment by means of clamping units or clamps. The clamping units are movably arranged on surrounding guide rails and are driven centrally or individually.

[0003] During the actual stretching process, large forces are applied to the clamps, subjecting them to extremely high loads. Therefore, special load requirements are imposed on the clamp units.

[0004] Therefore, manufacturing clamp units is very costly, as they are typically produced using casting methods such as investment casting, sand casting, or croningguss. Furthermore, clamp units have relatively complex and nested geometries with large cavities or voids. This makes it impossible to arrange them in a sealed manner on a casting tree, and further processing steps, such as galvanizing individual components, are difficult and costly. Summary of the Invention

[0005] Therefore, the objective of this invention is to provide a clamping unit and a stretching device having the clamping unit, which can be manufactured more simply and at a lower cost, while still meeting the high requirements of a stretching device.

[0006] The task is accomplished by a multi-piece clamping unit for a stretching device, particularly a transverse, longitudinal, and / or simultaneous stretching device, the multi-piece clamping unit having a main component and at least two guides. The main component has a base and clamping devices for clamping the material width, and each guide has a base and at least one guide element for guiding along a track on the stretching device. The bases of the guides and the main component are manufactured as separate components and fixed to each other. The bases of each guide and the main component are made of metal and manufactured by casting. The clamping unit has a main direction, and the bases of each guide are fixed to the main component by means of threaded members extending parallel to the main direction.

[0007] By designing the clamp unit into a multi-piece configuration with one main component and two guides, smaller individual units are provided, thereby significantly reducing the complexity of individual components. This allows for tighter and therefore denser assembly on the casting tree, for example, in casting methods.

[0008] Furthermore, it reduces the cost of additional processing steps, because, for example, in galvanizing, the cost is related to the size of the surface.

[0009] The inventors recognize that a clamping unit with at least three parts can meet all the requirements for the load limits proposed for clamping units used in stretching equipment, even though the clamping unit is divided into a main part and at least one separate guide.

[0010] Here, the base section of the main component can form the section of the clamping device.

[0011] In particular, the clamping device has at least one mersherlappe that is rotatably fixed to the base of the main component.

[0012] For example, the base of the guide and / or the base of the main component are made of metal and / or manufactured by forming. In this way, the load characteristics of the clamp unit can be further improved.

[0013] For example, the base of the guide and the base of the main component are cast or forged as separate components.

[0014] The clamp unit may have a main direction, in particular, the base of the guide extends parallel to the main direction in order to effectively absorb the load.

[0015] The main direction is, for example, a direction that is particularly horizontal, extending transversely to the material width within the edges accommodated in the clamping unit, or more precisely, the clamping device.

[0016] In the design of this invention, the contact surface extends perpendicularly to the main direction between the base of one of the guides and the base of the main member, thereby achieving a particularly load-bearing fixation.

[0017] In particular, the main part of the contact surface extends perpendicular to the main direction.

[0018] To easily and reliably secure the base, the base of the guide can be fixed to the main component by means of the threaded part of the clamp unit, in particular, the threaded part extends parallel to the main direction.

[0019] Threaded components are designed, for example, to withstand maximum forces between 700N and 900N, especially 800N. It is also conceivable that threaded components can withstand even higher forces.

[0020] Threaded parts can be mating threaded parts.

[0021] In one embodiment, the clamping unit has a U-shape, the U-shape having a base and two legs, specifically, the base of the main component forms the base and the base of the guide component forms one of the legs. The use of the U-shape results in a particularly stable clamping unit.

[0022] U-shapes are particularly present in side views and / or cross-sections.

[0023] The base can extend perpendicular to the main direction and / or the legs can extend parallel to the main direction.

[0024] The guide elements extend in particular parallel to each other.

[0025] The main component may have a material side and a guide side, wherein the clamping device is disposed on the material side and / or the guide is fixed to the main component on the guide side. In this way, the functions of the clamping unit can be clearly separated.

[0026] These sides should be understood as sides in the main direction.

[0027] In one embodiment, the clamping unit has a receiving portion that is at least limited by a guide, wherein the contact surface of the substrate is arranged between the clamping device and the receiving portion, thereby significantly reducing the empty volume during forming.

[0028] Within the scope of this invention, the contact surface of the substrate is understood as the contact surface between the substrate of one of the guides and the substrate of the at least one main component.

[0029] The contact surface is located, especially in the main direction, between the clamping device and the receiving part.

[0030] To further simplify the geometry, the receiving portion may be arranged in front of the guide side of the main component and / or the main component and the guide component may define the receiving portion.

[0031] In one embodiment, at least one fixing element for fixing the guide element and / or drive element is constructed on the base of the guide, and in particular, the at least one fixing element may be adjacent to and / or extend into the receiving portion, thereby simplifying the installation of the clamp unit.

[0032] To ensure reliable and safe guidance of the clamping unit on the track, the guiding element may be a roller, a sliding element, and / or a magnetic element, and / or the driving element may be a chain, a chain component, a linear motor component, and / or an engaging protrusion of a drive belt for the drive system of the stretching device.

[0033] Magnetic components are, for example, permanent magnets or ferromagnetic mating parts for magnets.

[0034] Furthermore, the task is solved by a stretching device, particularly a transverse, longitudinal and / or simultaneous stretching device, the stretching device having a track and at least one multi-piece clamping unit as described above, wherein the clamping unit is guided on the track by means of a guiding element.

[0035] The features and advantages discussed regarding clamp units also apply to stretching equipment, and vice versa. Attached Figure Description

[0036] Further features and advantages of the invention will become apparent from the following description and from the accompanying drawings, in which it is referred. The drawings show:

[0037] Figure 1 A schematic diagram of a first embodiment of the stretching device according to the present invention is shown.

[0038] Figure 2 A schematic diagram of a second embodiment of the stretching device according to the present invention is shown.

[0039] Figure 3 , Figure 4 A perspective view or side view of a first embodiment of the clamping unit according to the present invention is shown.

[0040] Figure 5 Showing according to Figure 3 The independent base of the clamp unit,

[0041] Figure 6 Shown in a perspective view according to Figure 4 The base of the main component of the clamping unit, and

[0042] Figure 7 A side view of a second embodiment of the clamping unit according to the present invention is shown. Detailed Implementation

[0043] The stretching equipment 10 has a furnace 14 and two drive systems 16.

[0044] The drive system 16 is arranged to be mirror-symmetrical with respect to the axis of symmetry S of the stretching device 10 and extends at least partially within the furnace 14. The drive system 16 extends outside the furnace 14 in the input area 18 and output area 20 of the material web 12 of the stretching device 10 for supplying or discharging.

[0045] In addition to input area 18 and output area 20, the stretching device has at least three other areas 22, 24, and 26.

[0046] Zones 22, 24, and 26 are adjacent to each other, such that when viewed along the normal direction of movement R or the pull-out direction R of the stretching device 10, first zone 22, then zone 24, then zone 26, and finally output zone 20 is adjacent to input zone 18.

[0047] In the first zone 22 (also known as the preheating zone) of the adjacent input zone 18 of the stretching device 10, the drive systems 16 have a first distance from each other.

[0048] In the second zone 24 (also known as the stretching zone), the distance between the two drive systems 16 increases until a second distance is finally reached at the beginning of the third zone 26 (also known as the heat treatment zone).

[0049] Each drive system in drive system 16 has a track 17 in a manner known per se, on which multiple clamping units 28 are guided. The clamping units 28 can move along the track 17 by being driven by their respective drive systems 16.

[0050] exist Figure 1 and Figure 2 In the diagram, each drive system 16 is shown only symbolically with two clamping units 28. However, the stretching device 10 has more clamping units 28.

[0051] The tracks 17 of each drive system 16 describe a closed path from the input zone 18 to the output zone 20 and back. The track segments constituting the preparation stage extend within the furnace 14 between the input zone 18 and the output zone 20 along the direction of movement of the clamping unit 28.

[0052] In the illustrated embodiment, the track section extending from the output zone 20 to the input zone 18 in the normal operating direction and forming a recirculation path is also arranged inside the furnace 14. However, as... Figure 2 As shown in the implementation, the track section can also be arranged outside the furnace 14.

[0053] In order to operate the stretching device 10, the material web 12 to be stretched is supplied to the stretching device 10 in the input area 18 along the stretching direction R. For this purpose, the material web 12 is fixed to the two drive systems 16 by means of its edges extending in the stretching direction R.

[0054] More precisely, the edge of the material sheet 12 is clamped by the clamping device 30 of the clamping unit 28. Figure 3 It is fixed and thus moves along the track 17 of the drive system 16 by the movement of the clamp unit 28.

[0055] In the input area 18, the material sheet 12 has a width E perpendicular to the pull-out direction R, which roughly corresponds to the first distance between the drive systems 16.

[0056] The material web 12 is then guided through the first zone 22 and heated in the first zone. In the adjacent second zone 24, i.e., the stretching zone, the material web 12 is stretched as the distance of the drive system 16 continuously increases. At the end of the second zone 24, the material web 12 has a second width A.

[0057] After stretching is completed, the material web 12 now passes through the third zone 26, where relaxation of the material web 12 can be performed before it is released by the clamping unit 28 in the output zone 20 and before it leaves the stretching device 10 with width A.

[0058] For example, stretching equipment 10 is a film-width stretching layer or a transverse stretching layer, which is abbreviated as TDO (TDO = transverse direction oven).

[0059] It is also conceivable that the stretching device 10 is a simultaneous stretching device, wherein the material width 12 in the second zone 24 (i.e. the stretching zone) can be stretched not only in the direction transverse to the stretching direction R but also in the stretching direction R.

[0060] During the processing of material width 12, a large tensile force is first applied to clamp unit 28 in the second zone 24, i.e., the stretching zone, along the stretching direction. The stretching direction has a major component in the main direction P of clamp unit 28 and a smaller component transverse to the main direction P.

[0061] Therefore, the clamping unit 28 must be constructed to withstand the high tensile forces that occur, especially in the main direction P of the clamping unit.

[0062] Here, the main direction P is a horizontal direction that extends laterally to the edge of the material sheet 12 housed in the clamping unit 28.

[0063] exist Figure 3 and Figure 4 In the diagram, one of the clamping units 28 is shown exemplarily in a perspective view or in part in a cross-section as a side view.

[0064] The clamp unit 28 has a main component 32 and two guides 34, wherein the main component 32 and the guides 34 are formed as independent components and subsequently fixed to each other. The clamp unit 28 is therefore multi-piece.

[0065] The main component 32 has a base 36 and a clamping device 30.

[0066] The side of the substrate 36 where the clamping device 30 is provided is also called the material side. The other side, that is, the side of the substrate 36 without the clamping device 30, is called the guide side, because the guide 34 is fixed on this side.

[0067] Therefore, the main component 32 also has a material side and a guide side.

[0068] In the illustrated embodiment, the clamping device 30 is constructed in a manner known per se from a section of the base 36 and a blade cap 38 rotatably fixed to the base 36.

[0069] The clamping device 30 defines a fixed section 40 or a fixed opening, into which the edge of the material sheet 12 to be fixed can be introduced and fixed to the clamping unit 28 by means of the blade cover 38.

[0070] The principal direction P of the clamping unit 28 is perpendicular to the edge or ridge of the material sheet, which is fixed in the clamping unit 28. Figure 4 Extending from the center to the left.

[0071] The substrate 36 is, for example, galvanized or nickel-plated in at least the area of ​​the fixed section 40.

[0072] The fixed material width 12 applies tension along the pulling direction to the clamp unit 28 in the second zone 24 (tension zone).

[0073] The guide 34 has a base 42 and at least one corresponding guide element 44 fixed on the base 42.

[0074] In the first embodiment, the guide 34 further includes a drive element 46, which is, for example, a chain or a component of the drive system 16.

[0075] The drive element 46 may also be an engaging protrusion of a component of a drive belt or linear motor for the drive system 16.

[0076] In the illustrated embodiment, the guide element 44 is configured as a roller. However, in other embodiments, the guide element 44 may also be a sliding element and / or a magnetic element, such as a permanent magnet or a ferromagnetic mating element.

[0077] The guide 34 defines a receiving portion 48 for the track 17 (also called a guide rail). In particular, notches can be provided in the base 42 of the guide 34, into which the track 17 is fitted.

[0078] Accordingly, the receiving part 48 is arranged in front of or above the guide side of the main component 32.

[0079] The guide element 44, especially the roller and, if necessary, the sliding element, can extend into the receiving part 48 and abut against the track 17 and serve as a guide on the track.

[0080] exist Figure 5 The base 36, 42 of the main component 32 or guide 34 are shown separately and individually, for example, directly after the base is manufactured, for example, after molding.

[0081] exist Figure 6 From the guide side, only the base 36 of the main component 32 is shown.

[0082] The substrates 36 and 42 are made of metal, such as G26CrMo4 or G42CrMo4, and are manufactured or machined by casting, forging or other methods.

[0083] In addition, the base 42 of the guide 34 has fixing elements 58, such as protrusions, notches and / or recesses, on which the guide element 44 and / or drive element 46 can be fixed.

[0084] The fixing element 58 may be adjacent to or extend into the receiving portion 48.

[0085] The base 42 of the guide 34 and the base 36 of the main component 32 are abutted against each other on the abutment surface 50 and are fixed to each other by means of the threaded part 52 of the clamp unit 28, for example, a mating threaded part.

[0086] The threaded component 52 is designed, for example, to withstand a maximum force between 700 N and 900 N, especially 800 N. It is also conceivable that the threaded component can withstand even higher forces.

[0087] As in Figure 4 As can be seen, threaded part 52 (approximately) extends parallel to the main direction P. The mating surface 50 extends perpendicular to the main direction P, as shown in... Figure 6 For example, as can be seen on the base 36 of the main component 32.

[0088] Therefore, the contact surface 50 is arranged along the main direction P between the clamping device 30 and the receiving part 48.

[0089] Therefore, the base 42 of the guide 34 is disposed on the guiding side of the main member 32 and extends from the base 36 of the main member 32 parallel to the main direction P. The guide 34, or its base 42, thus extends parallel to each other.

[0090] The bases 36 and 42 of the main component 32 or guide 34 together form a U-shape (in the side view and / or in the cross-section through the clamping unit 28), so that the clamping unit 28 has a U-shape.

[0091] The U-shape has a base 54 and two legs 56, wherein, in the illustrated embodiment, the base 54 is formed by the base 36 of the guide 34 and the legs are each formed by one of the bases 42 of the guide 34.

[0092] The base 54 extends perpendicularly to the leg 56. The leg 56 extends again parallel to the main direction P.

[0093] Because the substrates 36 and 42 each have a compact geometry that is significantly less complex than the entire clamping unit 28 (the substrate 42 of the guide 34 can be considered plate-like in the broadest sense), more substrates 36 and 42 can be placed on the casting tree, thereby significantly reducing manufacturing costs, for example, compared to a one-piece or, if necessary, two-piece clamping unit. Furthermore, the cost of casting three substrates is significantly lower because the geometry can be designed more simply.

[0094] By implementing the substrates 36 and 42 separately, the manufacturing of the substrates 36 and 42 is greatly simplified. Additional required process steps, such as galvanizing the substrate 36 in the area of ​​the fixed section 40, can also be performed more simply and thus at a lower cost.

[0095] exist Figure 7 Another embodiment of the invention is shown below. This other embodiment substantially corresponds to the aforementioned embodiment of the clamp unit 28, and therefore only the differences will be discussed below. Identical and functionally identical components are given the same reference numerals.

[0096] exist Figure 7 China and Israel are similar Figure 4 A partial cross-sectional view shows the multi-piece clamp unit 28 according to the second embodiment.

[0097] Compared to the first embodiment, the threaded part 52 used to fix the base 42 of one of the guides 34 to the main part 32 does not extend parallel to the main direction P but is inclined relative to the main direction.

[0098] In addition, the surface 50 (in) Figure 7 (Highlighted in the middle) It not only has sections perpendicular to the main direction P, but also has sections parallel to the main direction P. This simplifies installation and also improves the stability of the clamp unit 28.

[0099] However, the main part of the contact surface 50 extends perpendicular to the main direction P.

Claims

1. A multi-piece clamp unit for a stretching device (10), the clamp unit having a main component (32) and at least two guides (34). in, The main component (32) has a base (36) and a clamping device (30) for clamping the material web (12), and each of the guides (34) has a base (42) and at least one guide element (44) for guiding on the track (17) of the stretching device (10), and In this embodiment, the base (42) of each guide (34) and the base (36) of the main component (32) are manufactured as separate components and fixed together. The base (42) of each guide (34) and the base (36) of the main component (32) are made of metal and manufactured by casting. The clamp unit (28) has a main direction (P), and the base (42) of each guide (34) is fixed to the main member (32) by means of the threaded part (52) of the clamp unit (28), the threaded part (52) extending parallel to the main direction (P).

2. The clamping unit according to claim 1, characterized in that, The base (42) of each of the guides (34) extends parallel to the main direction (P).

3. The clamp unit according to claim 2, characterized in that, The abutment surface (50) between the base (42) of one of the guides (34) and the base (36) of the main member (32) extends perpendicular to the main direction (P).

4. The clamp unit according to any one of claims 1 to 3, characterized in that, The clamp unit (28) has a U-shape, which has a base (54) and two legs (56).

5. The clamp unit according to claim 4, characterized in that, The base (36) of the main component (32) forms the base (54), and the base (42) of each guide (34) forms one of the legs (56).

6. The clamp unit according to any one of claims 1 to 3, characterized in that, The main component (32) has a material side and a guide side, wherein the clamping device (30) is disposed on the material side, and / or each of the guides (34) is fixed on the main component (32) on the guide side.

7. The clamp unit according to any one of claims 1 to 3, characterized in that, The clamping unit (28) has a receiving portion (48) that is at least bounded by each of the guides (34), wherein the abutting surfaces (50) of the base (36) of the main member (32) and the base (42) of the guide (34) are arranged between the clamping device (30) and the receiving portion (48).

8. The clamp unit according to claim 7, characterized in that, The receiving portion (48) is arranged in front of the guide side of the main component (32), and / or the main component (32) and each of the guides (34) define the receiving portion (48).

9. The clamp unit according to any one of claims 1 to 3, characterized in that, At least one fixing element (58) for fixing the guide element (44) and / or drive element (46) is constructed on the base (42) of each of the guide elements (34).

10. The clamp unit according to claim 7, characterized in that, At least one fixing element (58) for fixing the guide element (44) and / or drive element (46) is constructed on the base (42) of each of the guide elements (34), and the at least one fixing element (58) is adjacent to the receiving portion (48) and / or extends into the receiving portion (48).

11. The clamp unit according to any one of claims 1 to 3, characterized in that, The guide element (44) is a roller, a sliding element, and / or a magnetic element.

12. The clamp unit according to claim 9, characterized in that, The drive element (46) is a chain, a chain component, a linear motor component, and / or an engagement protrusion of the drive belt of the drive system (16) for the stretching device (10).

13. The clamp unit according to any one of claims 1 to 3, characterized in that, The stretching device (10) is a transverse stretching device, a longitudinal stretching device, and / or a simultaneous stretching device.

14. A stretching device having a rail (17) and at least one multi-piece clamping unit (28) according to any one of claims 1 to 13, wherein, The clamp unit (28) is guided on the track (17) by means of the guide element (44).

15. The stretching device according to claim 14, characterized in that, The stretching device (10) is a transverse stretching device, a longitudinal stretching device, and / or a simultaneous stretching device.

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