Devices and units for laterally stretching elastic films

Abstract

A stretching device (12, 14) for laterally stretching elastic films (84, 86) is disclosed, the stretching device comprising: a first stretching member (16) and a second stretching member (18) having corresponding first and second rotation axes (20, 22) inclined relative to each other, and a drive assembly (30) for driving the first stretching member (16) and the second stretching member (18) to rotate about the corresponding rotation axes (20, 22), wherein the drive assembly (30) extends only on one side relative to the first stretching member (16, 18).

Description

Technical Field

[0001] This invention relates to the production of elastic laminates.

[0002] This invention is specifically developed for the production of elastic laminates intended for use in the manufacture of hygiene products (such as absorbent hygiene products, elastic bands for dressings, etc.).

[0003] More specifically, the present invention relates to an apparatus and unit for laterally stretching at least one elastic film sandwiched between two nonwoven webs. Background Technology

[0004] In order to manufacture hygiene products (such as diapers and other absorbent products), components with different properties are assembled together, such as absorbent core, back layer, top layer, elastic waistband, elastic side panels, closure structure, elastic barrier for the legs (leg brace), etc.

[0005] Some components of absorbent hygiene products (such as elastic bands for the legs, elastic leg barriers, elastic side panels, elastic waistbands, etc.) are made of elastic laminates.

[0006] Depending on the characteristics of absorbent hygiene products, elastic laminates can be manufactured in various ways. For example, some types of elastic laminates can be formed from one or more nonwoven webs bonded to an elastic film. In some applications, the elastic film is stretched in the transverse direction before being secured between two opposing nonwoven webs.

[0007] EP3496687 A1 describes a method and apparatus for assembling resilient laminated articles, wherein a first nonwoven web is wound on the outer cylindrical surface of an anvil rotating about a rotation axis, a first elastic film and a second elastic film are stretched in a transverse direction on a first stretching device and a second stretching device, and applied to the first nonwoven web on the anvil in a first application area and a second application area that are axially and angularly displaced relative to the rotation axis, a second nonwoven web is fed to the anvil above the first elastic film and the second elastic film stretched in the transverse direction, and the first nonwoven web and the second nonwoven web are ultrasonically welded together through the first elastic film and the second elastic film and in a central portion included between the first elastic film and the second elastic film.

[0008] Other similar solutions are disclosed in EP3496688, EP3496689, and EP3496690.

[0009] In the solution described in EP3496687 A1, a first and a second elastic film, stretched in the transverse direction, are applied to the nonwoven web in two regions that are angularly offset from each other. This leads to difficulties in positioning the elastic films relative to the nonwoven web and raises issues regarding ensuring precise spacing between the two elastic films. Furthermore, arranging two stretching units in two different regions involves large dimensions of the manufacturing line, which may not be compatible with the dimensions of the manufacturing plant.

[0010] Existing tensioning devices are typically such as those described in EP2260813 B1. Figure 2 The diagram illustrates a pair of tension members that rotate about corresponding axes of rotation that are inclined relative to each other, each driven by a corresponding motor that protrudes on opposite sides relative to a central plane extending between the two tension members. This arrangement requires the operator to perform setup and adjustment operations on both sides of the unit. These operations are often interrelated, and therefore, it is typically necessary to set or adjust on one side of the unit before setting or adjusting on the other side.

[0011] Another problem with existing equipment used for producing elastic laminates is its lack of flexibility. Current stretching units form only one type of elastic laminate. If a manufacturer intends to expand its product range, it typically needs to install a separate manufacturing line for each type of product it wants to commercialize. Summary of the Invention

[0012] The present invention aims to provide a stretching device and a stretching unit that overcome the problems of the prior art.

[0013] According to the present invention, this objective is achieved by a stretching device and a stretching unit. Attached Figure Description

[0014] The invention will now be described in detail with reference to the accompanying drawings. The drawings are given by way of non-limiting example only, in which:

[0015] - Figure 1 This is a schematic perspective view of the stretching unit;

[0016] - Figure 2 This is a partial cross-sectional perspective view of the tension element;

[0017] - Figure 3 It is along Figure 1 A cross-sectional view taken from line III-III;

[0018] - Figure 4 This is a schematic diagram of a first embodiment of equipment for producing elastic laminated products;

[0019] - Figure 5 It is shown Figure 4A schematic floor plan of the equipment in operation;

[0020] - Figure 6 This is a schematic diagram of a second embodiment of equipment for producing elastic laminated products; and

[0021] - Figure 7 , Figure 8 , Figure 9 , Figure 10 These are schematic cross-sectional views of various embodiments of elastic laminated articles that can be produced using the equipment and methods disclosed herein.

[0022] It should be understood that in order to simplify the understanding of the diagrams, some components may not be shown, and the diagrams may not be represented at the same scale. Detailed Implementation

[0023] refer to Figures 1-3 The number 10 indicates a stretching unit, which is used to stretch the continuous elastic film in a direction transverse to the longitudinal direction of the continuous elastic film.

[0024] The stretching unit 10 includes a first stretching device 12 and a second stretching device 14. The first stretching device 12 and the second stretching device 14 are substantially the same as each other.

[0025] Each of the first tensioning device 12 and the second tensioning device 14 includes a first tensioning member 16 and a second tensioning member 18, which are about corresponding first rotation axes 20 and second rotation axes 22 that are inclined relative to each other. Figure 3 Rotate.

[0026] As shown in the figure, the first tension member 16 and the second tension member 18 can be disc-shaped. In a possible embodiment, the first tension member 16 and the second tension member 18 can have shapes different from those of a disc.

[0027] The first tension member 16 and the second tension member 18 have corresponding outer edges 24, 26, which are provided with clamping elements for holding the respective side edges of the elastic film. The clamping elements may be suction holes 28 opening on the outer edges 24, 26, and the clamping elements are connected to a pressure source below atmospheric pressure, as will be disclosed below. As an alternative to or supplement to the suction holes 28, the outer edges 24, 26 of the tension members 16, 18 may be provided with protruding pins that engage the side edges of the elastic film.

[0028] refer to Figures 1-3Each of the first tensioning device 12 and the second tensioning device 14 includes a corresponding drive assembly 30. The drive assembly is configured to drive the corresponding first tensioning member 16 and the second tensioning member 18 to rotate about corresponding rotation axes 20 and 22.

[0029] The drive assembly 30 of each of the first tensioning device 12 and the second tensioning device 14 is arranged on only one side relative to the corresponding tensioning member 16, 18. More specifically, the first tensioning member 16 and the second tensioning member 18 of the first tensioning device 12 and the second tensioning device 14 are located distally and proximally relative to the corresponding drive assembly 30, respectively, and the drive assembly 30 extends on only one side relative to the first tensioning member 16.

[0030] In the embodiment shown in the accompanying drawings, the drive assembly 30 of each of the first tensioning device 12 and the second tensioning device 14 includes a first motor 32 and a second motor 34 that respectively drive the first tensioning member 16 and the second tensioning member 18. Each motor 32, 34 may include a corresponding reduction gear. In each of the first tensioning device 12 and the second tensioning device 14, the two motors 32, 34 are arranged on only one side relative to the corresponding tensioning member 16, 18.

[0031] In a possible embodiment, the drive assembly 30 of each of the first tensioning device 12 and the second tensioning device 14 may include a single motor and a connector assembly connecting the single motor to the corresponding first tensioning member 16 and the second tensioning member 18. In this embodiment, in each of the first tensioning device 12 and the second tensioning device 14, the single motor and the connector assembly are arranged on only one side relative to the corresponding tensioning members 16, 18.

[0032] The first motor 32 can be coaxial with the corresponding first tension member 16 and can be connected to the first tension member via the first shaft 36. The second motor 34 can be eccentric with the corresponding second tension member 18 and can be connected to the second tension member via the second shaft 38 and a belt drive including a toothed belt 40 and a pair of toothed pulleys.

[0033] refer to Figures 1-3Each of the first tension member 16 and the second tension member 18 has a suction port 28 communicating with a plurality of connection ports, which open on the side surfaces of the corresponding first tension member 16 and the second tension member 18 facing the drive assembly 30. The connection ports of each of the first tension member 16 and the second tension member 18 are pneumatically connected to corresponding fixed suction chambers 44, 46, the opening sides of which face forward toward the side surfaces of the corresponding first tension member 16 and the second tension member 18, and the connection ports open on these side surfaces. The suction chambers 44, 46 are connected to a pressure source below atmospheric pressure via corresponding tubular elements 48, 50 and flexible tubes (not shown). The suction chambers 44, 46 of the first tension device 12 and the second tension device 14 are arranged on the side surfaces of the corresponding tension members 16, 18 facing the corresponding drive assembly 30.

[0034] In one possible embodiment, the fixed suction chambers 44 and 46 of the first stretching device 12 and the second stretching device 14 are coaxial with the corresponding first stretching member 16 and the second stretching member 18.

[0035] In one possible embodiment, the suction chamber 44 of the first stretching device 12 and the second stretching device 14 is connected to the stretching member 16 located distal to the corresponding drive assembly 30. The suction chamber can be selectively connected and disconnected from a pressure source below atmospheric pressure, so that the stretching unit 10 can operate only with the external stretching member 18, while the internal stretching member 16 does not operate.

[0036] refer to Figures 1-3 Each of the first tensioning device 12 and the second tensioning device 14 includes a first adjustment mechanism 52 and a second adjustment mechanism 54 correspondingly associated with the first tensioning member 16 and the second tensioning member 18.

[0037] Each of the first adjustment mechanism 52 and the second adjustment mechanism 54 is configured to adjust the tilt angle of the rotation axis 20 of the corresponding first tension member 16 and the rotation axis 22 of the corresponding tension member 18.

[0038] The first adjustment mechanism 52 and the second adjustment mechanism 54 of the first tensioning device 12 and the second tensioning device 14 are arranged on the side of the corresponding first tensioning member 16 and the second tensioning member 18 facing the corresponding drive assembly 30.

[0039] refer to Figure 1 and Figure 2Each of the first adjusting mechanism 52 and the second adjusting mechanism 54 includes a base 56 and an adjustable support structure 58. The angular position of the adjustable support structure 58 relative to the base 56 can be adjusted about a corresponding adjusting axis 60. The angular movement of the adjustable support structure 58 about the adjusting axis 60 can be controlled by a manual actuation lever 62 or a motor (not shown).

[0040] Each adjustable support structure 58 rotatably supports the corresponding first axis 36 or second axis 38. Therefore, adjusting the angle of the adjustable support structure 58 around the adjustment axis 60 changes the inclination of the corresponding first rotation axis 20 or second rotation axis 22.

[0041] The fixed suction chambers 44, 46 of each of the first stretching device 12 and the second stretching device 14 are supported by the adjustable support structures 58 of the corresponding first adjusting mechanism 52 and second adjusting mechanism 54. Therefore, when the inclination of the rotation axis 20 of the first stretching member 16 and the rotation axis 22 of the second stretching member 18 is adjusted, the relative positions between the first stretching member 16 and the second stretching member 18 and the corresponding fixed suction chambers 44, 46 will not change.

[0042] The base 56 of each of the first adjustment mechanism 52 and the second adjustment mechanism 54 may include a corresponding guide 64, which allows the position of the corresponding first adjustment mechanism 52 and the second adjustment mechanism 54 to be adjusted along the lateral direction Y.

[0043] Each of the first adjustment mechanism 52 and the second adjustment mechanism 54 may include an auxiliary adjustment device 66 that allows adjustment of the position of the corresponding first tension member 16 and the second tension member 18 along linear directions X and / or Z orthogonal to the lateral direction Y. The auxiliary adjustment device 66 may be manually controlled or controlled by a corresponding motor (not shown).

[0044] refer to Figure 3 Each of the first tensioning device 12 and the second tensioning device 14 has a corresponding clamping area 68 and a corresponding release area 70.

[0045] The first tensioning member 16 and the second tensioning member 18 of each of the first tensioning device 12 and the second tensioning device 14 are spaced apart from each other in the lateral direction Y, spaced apart by a first distance W1 in the clamping area 68, and spaced apart by a second distance W2 in the release area 70, the second distance W2 being greater than the first distance W1. The distances W1 and W2 of the first tensioning device 12 and the second tensioning device 14 may be equal or different.

[0046] For details, please refer to the following: Figure 2 and Figure 3The release areas 70 of the first tensioning device 12 and the second tensioning device 14 are aligned with each other along a common transverse release line 72.

[0047] refer to Figure 3 The first tensioning device 12 and the second tensioning device 14 are arranged on opposite sides of a central plane 74 orthogonal to a common transverse release line 72. The two first tensioning members 16 of the first tensioning device 12 and the second tensioning device 14 (located on the far side relative to the corresponding drive assembly 30) face the opposite sides of the central plane 74.

[0048] In each of the first stretching device 12 and the second stretching device 14, the corresponding drive assembly 30, fixed suction chambers 44, 46, and adjusting mechanisms 52, 54 extend only on one side of the central plane 74. The drive assembly 30, fixed suction chambers 44, 46, and adjusting mechanisms 52, 54 of the first stretching device 12 and the second stretching device 14 extend on opposite sides of the central plane 74.

[0049] refer to Figure 4 Equipment used for producing elastic laminated products is indicated by reference numeral 76 in the attached drawing.

[0050] The device 76 includes a first feeding device 78 configured to feed the single continuous elastic film 80 along a direction X parallel to the longitudinal axis of the single continuous elastic film 80.

[0051] The device 76 includes a stretching unit 10 as previously described, which includes a first stretching device 12 and a second stretching device 14.

[0052] In the longitudinal cutting unit 82, a single continuous elastic film 80 is longitudinally cut to form a first continuous elastic film 84 and a second continuous elastic film 86, which are then fed to the stretching unit 10 via a second feeding device 88.

[0053] Device 10 includes an anvil 90 rotatable about a transverse axis of rotation. The anvil 90 has an outer cylindrical surface disposed at a pressure source 91 below atmospheric pressure. Figure 5 The suction port is pneumatically connected. The outer cylindrical surface of the anvil wheel 90 is tangent to the common transverse release line 72 of the tension unit 10.

[0054] The apparatus 10 includes a third feed device 92 and a fourth feed device 94, which are configured to feed a first nonwoven web 96 and a second nonwoven web 98 to an anvil 90, respectively. In a possible embodiment, each of the third feed device and the fourth feed device 94 may feed two parallel first nonwoven webs 96 and two parallel second nonwoven webs 98 to the anvil 90.

[0055] refer to Figure 4 The direction of rotation of the anvil wheel 90, indicated by arrow 100, is upstream of the common transverse release line 72 of the tensioning unit 10, where a first nonwoven web 96 or two parallel first nonwoven webs 96 are applied to the anvil wheel 50, and downstream of the common transverse release line 72, a second nonwoven web 98 or two parallel second nonwoven webs 98 are applied to the anvil wheel 90.

[0056] The device 76 includes a fastening device 102 that mates with the outer cylindrical surface of the anvil wheel 90. The fastening device 102 may be an ultrasonic welding device, a pressure device for fastening by adhesive, a thermal welding device, or a thermomechanical welding device.

[0057] The operation of the previously described device 76 is as follows.

[0058] A single continuous elastic film 80 is unrolled from a spool and longitudinally cut to form a first continuous elastic film 84 and a second continuous elastic film 86. The first continuous elastic film 84 and the second continuous elastic film 86 may have corresponding widths W1 that are equal to or different from each other. In possible embodiments, the first continuous elastic film 84 and the second continuous elastic film 86 may be unrolled from corresponding spools. The first continuous elastic film 84 and the second continuous elastic film 86 may be the same as or different from each other; for example, they may be made of materials with different elastic properties.

[0059] refer to Figure 5 The lateral edges of the first continuous elastic film 84 and the second continuous elastic film 86 are held by the outer edge 24 of the corresponding first stretching device 12 and the outer edge 26 of the second stretching device 14 of the stretching unit 10.

[0060] The first stretching device 12 and the second stretching device 14 pick up a first continuous elastic film 84 and a second continuous elastic film 86, each having a corresponding first width W1, in their respective clamping areas 68, and rotate about their respective rotation axes 20 and 22. During the rotation of the stretching members 16 and 18, the two continuous elastic films 84 and 86 are stretched in the lateral direction Y along the path from the corresponding clamping area 68 to the corresponding release area 70. In the corresponding release area 70, the two continuous elastic films 84 and 86 have corresponding widths W2, which may be equal to or different from each other.

[0061] refer to Figure 4 The first nonwoven web 96 or two parallel first nonwoven webs 96 are applied to the outer cylindrical surface of the anvil 90 at or upstream of the common transverse release line 72.

[0062] The first continuous elastic film 84 and the second continuous elastic film 86, while being stretched along the transverse direction Y, separate from the outer edges 24 and 26 of the corresponding first stretching member 14 and the second stretching member 16, and are applied to the first nonwoven web 96 or to a corresponding parallel first nonwoven web 96 held in a corresponding release area 70 on the outer cylindrical surface of the anvil 90, the release areas being aligned along a common transverse release line 72. The first continuous elastic film 84 and the second continuous elastic film 86 are held in a transversely stretched state on the outer cylindrical surface of the anvil 90, for example, by suction.

[0063] The fact that the first continuous elastic film 84 and the second continuous elastic film 86 are applied along the common transverse release line 72 onto the first nonwoven web 96 or the corresponding parallel first nonwoven web 96 ensures high accuracy in the mutual positioning between the two continuous elastic films 84, 86 and the first nonwoven web 96.

[0064] After applying the first continuous elastic film 84 and the second continuous elastic film 86 to the first nonwoven web 96 or the corresponding parallel first nonwoven web 96 on the outer cylindrical surface of the anvil 90, the second nonwoven web 98 or two parallel second nonwoven webs 98 are applied to the anvil 90, positioned above the two parallel continuous elastic films 84, 86, such that the elastic films 84, 86, which are elastically stretched along the transverse direction Y, are sandwiched between the first nonwoven web 96 and the second nonwoven web 98 or between two pairs of first nonwoven webs 96 and second nonwoven webs 98.

[0065] Then, the nonwoven webs 96 and 98 are joined together by fastening device 102, through two parallel continuous first elastic films 84 and second elastic films 86 (e.g., by ultrasonic welding), thereby forming a continuous elastic laminate or two parallel continuous elastic laminates.

[0066] Connecting nonwoven webs 96 and 98 to each other via two parallel, continuous elastic films 84 and 86 includes directly fastening the nonwoven webs 96 and 98 through openings in the elastic films 84 and 86, and fastening the nonwoven webs 96 and 98 to opposite sides of the elastic films 84 and 86.

[0067] The fastening device 102 can be configured to form a plurality of connection points that form corresponding holes through the elastic films 84, 86, and directly secure the opposing nonwoven webs 96, 98 to each other through the holes formed in the elastic films 84, 86. The elastic films 84, 86 remain anchored to the nonwoven webs 96, 98 at the connection points extending through the holes formed in the elastic films 84, 86. The formation of holes through the elastic films 84, 86 provides a breathable, elastic laminate.

[0068] Figure 6 A second embodiment of an apparatus 76 for producing elastic laminated articles is shown. Components corresponding to those previously disclosed are indicated by the same reference numerals.

[0069] exist Figure 6 In one embodiment, the device 76 includes a transfer wheel 106 disposed between the stretching unit 10 and the anvil wheel 90. The transfer wheel 106 rotates about a rotation axis parallel to the rotation axis of the anvil wheel 90, and the transfer wheel has an outer cylindrical surface tangent to the outer cylindrical surface of the anvil wheel 90 along a transverse line.

[0070] The conveyor wheel 106 is provided with a clamping element configured to maintain a first continuous elastic membrane 84 and a second continuous elastic membrane 86 under lateral tension. In a possible embodiment, the clamping element may include a suction port opening on the outer cylindrical surface of the conveyor wheel 106, and the clamping element is pneumatically connected to a pressure source at sub-atmospheric pressure for maintaining the first continuous elastic membrane 84 and the second continuous elastic membrane 86 under lateral tension by suction. The clamping element may include a protruding pin as a supplement to or alternative to the suction port.

[0071] The stretching unit 10 applies a first continuous elastic film 84 and a second continuous elastic film 86, stretched laterally, to the outer cylindrical surface of the conveyor wheel 106 in a release area 70 aligned along a common transverse release line 72. In the release area 70, the first continuous elastic film 84 and the second continuous elastic film 86, stretched in the transverse direction Y, separate from the first stretching member 16 and the second stretching member 18 of the stretching unit 10, and are brought to the outer cylindrical surface of the conveyor wheel 106, for example, by suction.

[0072] Then, the first continuous elastic film 84 and the second continuous elastic film 86, stretched in the transverse direction Y, separate from the conveyor wheel 106 and are applied to the first nonwoven web 96 or two parallel first nonwoven webs 96 held on the outer cylindrical surface of the anvil wheel 90. In a possible embodiment, the first nonwoven web 96 or two parallel first nonwoven webs 96 can be applied to the outer cylindrical surface of the anvil wheel 90 by first applying the transversely stretched elastic films 84, 86 to the conveyor wheel 106.

[0073] exist Figure 6In this embodiment, two parallel, continuous elastic films 84, 86 (made of a non-porous material) are applied to directly contact the outer cylindrical surface of the transfer wheel 40 without the need for a porous material layer. This allows the continuous elastic films 84, 86 to be held in a laterally stretched state with high accuracy. Furthermore, the two parallel, continuous elastic films 84, 86 are transferred from the transfer wheel 106 to the anvil wheel 90 between two tangential cylindrical surfaces, which simplifies the transfer of the elastic films and avoids positioning errors that may occur when the elastic films are applied to the nonwoven web starting from a surface with an inclined axis.

[0074] refer to Figure 6 The device 76 may include at least one longitudinal cutting device 108. The longitudinal cutting device 108 is configured to cut a transversely stretched continuous elastic film 84, 86 held on the outer cylindrical surface of the conveyor wheel 106 along at least one longitudinal cutting line.

[0075] In one possible embodiment, the stretching unit 10 can apply a single continuous elastic film 80 to the conveyor wheel 106, where the single continuous elastic film is longitudinally cut. The single continuous elastic film 80 can be longitudinally cut along multiple parallel cutting lines to form more than two parallel continuous elastic films.

[0076] The longitudinal cutting device 108 may include a cutting disc 109 that rotates about an axis parallel to the axis of rotation of the conveyor wheel 106. The cutting disc 109 may engage with a corresponding circumferential slot formed on the outer cylindrical surface of the conveyor wheel 106.

[0077] In one possible embodiment, the device may include a longitudinal cutting device arranged to longitudinally cut one or more continuous elastic films on an anvil 90. The longitudinal cutting device can cut the elastic films without cutting the underlying nonwoven web.

[0078] The equipment according to the invention offers great flexibility in terms of the possibility of producing different types of elastic laminated products.

[0079] refer to Figure 7A first embodiment of the elastic laminate 110 includes a first continuous elastic film 84 and a second continuous elastic film 86 sandwiched between a first wide nonwoven web 96 and a second wide nonwoven web 98 and secured to the two nonwoven webs 96, 98 via a set of connection points 112. The elastic laminate 110 may have an inelastic portion 114 in which the elastic films 84, 86 are laterally spaced apart from each other, and the two nonwoven webs 96, 98 are in direct contact with each other. The two wide nonwoven webs 96, 98 are directly secured to each other in the inelastic portion 114, which includes the two parallel continuous elastic films 84, 86 and along the longitudinal edges outside the elastic films 84, 86. The fastening device 102 may be configured to achieve a uniform fastening pattern over the entire surface of the nonwoven webs 96, 98 at the elastic films 84, 86 and in the inelastic portion 114.

[0080] The device according to the invention may include a cutting unit configured to form a longitudinal weakening line on the inelastic portion 114, the weakening line forming a preferential fracture line that allows two elastic portions of the elastic laminate to separate from each other after a weak separation force is applied.

[0081] refer to Figure 8 According to the invention, the apparatus can produce two independent continuous elastic laminates 110, each continuous elastic laminate comprising a continuous elastic film 84, 86 sandwiched between a corresponding first narrow nonwoven web 96 and a second narrow nonwoven web 98. Figure 8 Two continuous elastic laminates 110 can be produced by feeding two separate first narrow nonwoven webs 96 and two separate second narrow nonwoven webs 98 onto an anvil, which are stacked onto corresponding first and second continuous elastic films 84 and 86.

[0082] exist Figure 7 and Figure 8 In the embodiments, the first continuous elastic film 84 and the second continuous elastic film 86 may have the same or different widths, the first continuous elastic film and the second continuous elastic film may be laterally stretched by the same or different stretching ratios W2 / W1, and the first continuous elastic film and the second continuous elastic film may be made of the same or different materials.

[0083] refer to Figure 9 The apparatus according to the invention can also produce an elastic laminate 110 having a single wide continuous elastic film 80 sandwiched between a first wide nonwoven web 96 and a second wide nonwoven web 98. Figure 9The elastic laminate 110 can be produced by laterally stretching a single continuous elastic film 80 by two second stretching members 18 of the stretching unit 10. The two first stretching members 16 of the stretching unit 10 can be disconnected from a pressure source below atmospheric pressure and moved in the X direction away from the common lateral release line 72, so that they do not interfere with the single continuous elastic film 80.

[0084] refer to Figure 10 The apparatus according to the invention can also produce an elastic laminate 110 having only a continuous elastic film 84 sandwiched between a first wide nonwoven web 96 and a second wide nonwoven web 98, the first wide nonwoven web and the second wide nonwoven web forming a wide inelastic portion 116 extending laterally to the continuous elastic film 84. Figure 10 The elastic laminate 110 can be produced by laterally stretching only a continuous elastic film 84 by two stretching members 16, 18 of only one stretching device 12 of the stretching unit 10. The inelastic portion 116 can extend to the left or right of the continuous elastic film 84. In one possible embodiment, the single continuous elastic film 84 can be centrally enclosed between two wide nonwoven webs 96, 98, which form a wide inelastic portion 116 extending laterally from opposite sides of the single continuous elastic film 84. In one possible embodiment, the single continuous elastic film 84 can be laterally encapsulated between a wide nonwoven web and a narrow nonwoven web.

[0085] The width of the wide nonwoven webs 96 and 98 is greater than the width of the first continuous elastic film 84 and the second continuous elastic film 86 arranged side by side, and the width of the narrow nonwoven webs 96 and 98 is less than the width of the wide nonwoven webs 96 and 98 but greater than the width of one continuous elastic film 84 and 86.

[0086] The device may include one or two winding units configured to wind one or two elastic laminates 110 onto one or two reels.

[0087] Of course, without prejudice to the principles of the invention, the details of the construction and embodiments may be varied extensively with respect to what is described and shown, without departing from the scope of the invention as defined by the appended claims.

Claims

1. A stretching device for laterally stretching an elastic film, comprising: - A first tension member and a second tension member, each having a clamping element at its corresponding outer edge, the clamping element being configured to clamp the corresponding edge of the elastic film, wherein the first tension member and the second tension member have corresponding first and second rotation axes, the first and second rotation axes being inclined relative to each other, and - A drive assembly configured to drive the first tension member and the second tension member to rotate about a corresponding axis of rotation, wherein the first tension member and the second tension member are respectively located on the far side and the near side relative to the drive assembly, and wherein the drive assembly includes a first motor and a second motor respectively connected to the first tension member and the second tension member, and wherein the drive assembly extends only on one side relative to the first tension member, such that the first motor and the second motor are arranged on the same side relative to the corresponding first tension member and the second tension member.

2. The tensioning device according to claim 1, wherein, The first motor is connected to the first tension member via a first shaft coaxial with the first rotation axis, and the second motor is eccentric relative to the second rotation axis and connected to the second tension member via a belt drive.

3. The tensioning device according to claim 1, wherein, The outer edge of each of the first and second tension members includes a plurality of suction holes pneumatically connected to the corresponding fixed suction chamber, wherein the fixed suction chamber is arranged on the same side relative to the corresponding first and second tension members.

4. The tensioning device according to claim 3, wherein, The fixed suction chamber is coaxial with the corresponding first tension member and second tension member.

5. The tensioning device according to claim 3, wherein, Each of the first and second tension members has a plurality of suction holes connected to a connecting hole, the connecting hole opening on the side surface of the corresponding first and second tension members facing the drive assembly, and wherein each of the suction chambers opens forward on the side surface of the corresponding first and second tension members.

6. The tensioning device according to claim 1, comprising a first adjusting mechanism and a second adjusting mechanism, wherein the first adjusting mechanism and the second adjusting mechanism are configured to adjust the tilt angle of the rotation axis of the corresponding first tensioning member and the second tensioning member.

7. The tensioning device according to claim 6, wherein, The first adjustment mechanism and the second adjustment mechanism each include an adjustable support structure, which carries the corresponding first tension member or second tension member, the corresponding first motor or second motor, and the corresponding first fixed suction chamber or second fixed suction chamber.

8. The tensioning device according to claim 7, wherein, The adjustable support structure of each of the first and second adjustment mechanisms can be adjusted to rotate around the corresponding adjustment axis relative to the corresponding base.

9. The tensioning device according to claim 8, wherein, The base of each of the first and second adjustment mechanisms can be adjusted by translation in the lateral direction.

10. The tensioning device according to claim 6, wherein, The first adjustment mechanism and the second adjustment mechanism each include an auxiliary adjustment device, which is configured to adjust the position of the corresponding first tension member or second tension member along a linear direction.

11. The tensioning device according to claim 1, wherein, Each of the first tension member and the second tension member is disc-shaped.

12. A stretching unit for laterally stretching an elastic film, the stretching unit comprising a first stretching device and a second stretching device, wherein the first stretching device and the second stretching device are the stretching devices according to claim 1, wherein... The first stretching device and the second stretching device have corresponding clamping areas and corresponding release areas, wherein the release areas of the first stretching device and the second stretching device are aligned with each other along a common transverse release line.

13. The tensioning unit according to claim 12, wherein, The first tensioning device and the second tensioning device are arranged on opposite sides of a central plane orthogonal to the common transverse release line, wherein the drive assembly extends only on one side of the central plane.

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