Method and apparatus for notching web material

Abstract

An apparatus for notching web material comprises a longitudinal cutting assembly (200) comprising a guide roller (201) rotatable about a respective axis (C), a first cutting member (202) and a second cutting member (203) downstream of the first cutting member (202). The first and second cutting members (202, 203) are operable independently of one another to move in an approaching or distancing manner between a first inactive position in which they are distanced from the web material (2) fed in operation between the guide roller (201) and the first and second cutting members (202, 203), respectively, and a second active position in which they are distanced from the web material (2) fed in operation between the guide roller (201) and the first and second cutting members (202, 203), respectively. In a second active position, they are adapted to engage with the web material (2) between the guide roller (201) and the first and second cutting members (202, 203) to punch a longitudinal cut (402) on the web material (2).

Description

Technical Field

[0001] The invention relates to a method for making cuts on the longitudinal edges of a web material, and to a device for carrying out the method. Background Art

[0002] It is known to use flexible web materials which are provided with a plurality of cuts on one or both of the respective longitudinal edges, the cuts being, for example, substantially perpendicular to the web element or inclined with respect to the longitudinal direction of the web element. The cuts can be made with a fixed spacing in the longitudinal direction of the web element, i.e. the cuts are equidistant from one another, or with a variable spacing, i.e. the cuts are unequally spaced from one another. Furthermore, the portion of the web element which is located between two consecutive cuts can be removed, thereby forming a cut-out profile of the longitudinal edge of the web element.

[0003] Web materials having longitudinal edges shaped in this manner are used, for example, in the field of production of electrical energy storage devices.

[0004] The longitudinal edges of the web material are punched out by a process called notching, which uses a mechanical or laser cutting device carried out in an automatic machine.

[0005] Devices for slitting web material are known, for example, from patents JP 2016001575 A and EP 3 404 745 A1.

[0006] In certain production areas, it is necessary to make the slitting operation of the web material very fast without damaging the sometimes very thin web material during this operation. At the same time, it must be ensured that the slitting operation of the web material is carried out with a high degree of precision.

[0007] Another demand is to have a versatile, economical and compact device for cutting web materials. In fact, in the devices known in the art, the devices used may be very bulky, or when it is necessary to change the cutting characteristics, the device needs to be replaced or installed in a laborious manner. Summary of the invention

[0008] The object of the present invention is to solve the above mentioned problems by devising a method which optimally allows for punching cuts in the longitudinal edges of a web material.

[0009] Within this aim, another object of the present invention is to provide a method for punching out cuts in the longitudinal edges of a web material running in an automatic machine, which method ensures that a high production speed is achieved.

[0010] Another object of the invention is to provide a method for punching cuts in the longitudinal edges of a web material which ensures that a high degree of precision is achieved.

[0011] Another object of the present invention is to provide a method for punching cuts in the longitudinal edges of a web material which method maintains the integrity of the web material.

[0012] Another object of the invention is to provide an apparatus capable of implementing the method of punching out cuts in the longitudinal edges of a web material, which apparatus has a simple structural and functional design, reliable operation, versatile use and relatively economical costs.

[0013] Another object of the invention is to provide a compact device which allows to easily vary the characteristics of the cuts to be punched.

[0014] According to the invention, the above objects are achieved by a device and a method for punching cuts in the longitudinal edges of a web material according to claims 1 and 6 .

[0015] The device for slitting a web material comprises a longitudinal cutting assembly including guide rollers rotatable about respective axes, a first cutting member and a second cutting member located downstream of the first cutting member.

[0016] Preferably, the first cutting member and the second cutting member can be moved independently of each other in a manner of approaching or moving away from each other between a first non-activated position and a second activated position, in which the first cutting member and the second cutting member are away from the web material, and in the second activated position, the first cutting member and the second cutting member are suitable for engaging with the web material fed between the guide roller and the first cutting member and between the guide roller and the second cutting member during operation to punch out longitudinal cuts on the web material.

[0017] Preferably, the first cutting member is shaped like a circular blade and the first cutting member is rotatable about a respective axis.

[0018] Preferably, the second cutting member is shaped like a circular arc blade, and the second cutting member is rotatable around a corresponding axis.

[0019] Preferably, the first and second cutting members are arranged at the ends of respective arms operable in a tilting movement.

[0020] A method of punching a shaped cut in a web material comprises feeding the web material to a longitudinal cutting assembly comprising a guide roller driven to rotate about an axis, a first cutting member and a second cutting member downstream of the first cutting member.

[0021] Subsequently, the method comprises moving the first cutting member from a first inactive position, in which the first cutting member is away from the web material, towards a second active position, in which the first cutting member is adapted to pre-engage the web material between the guide roller and the first cutting member to form a longitudinal cut in the web material.

[0022] Subsequently, the method includes moving the first cutting member from a second activated position in a distal manner to a first non-activated position, and activating the second cutting member in an appropriate phase relationship to move the second cutting member from the first non-activated position in a proximal manner to a second activated position, wherein the first cutting member is positioned away from the web material and the second activated position wherein the second cutting member is capable of engaging the web material traveling between the guide roller and the second cutting member to punch out a longitudinal cut to trim the edge of the previously punched longitudinal cut.

[0023] Finally, the method includes moving the second cutting device away from the second activated position to the first inactivated position.

[0024] Preferably, the second cutting device is activated in the second activated position in a phase relationship such that the second cutting device engages the edge to be trimmed of the previously punched longitudinal cut with a portion of the end of the corresponding cut edge. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Details of the invention will become apparent from the detailed description of a preferred embodiment of an apparatus for slitting a web material, shown by way of example in the accompanying drawings, in which:

[0026] Figure 1 is a schematic side view of an apparatus for slitting web material according to the present invention;

[0027] Figure 2 is a plan view of a portion of a web material according to the present invention having a cutout;

[0028] Figure 3 yes Figure 1 A magnified view of the details;

[0029] Figure 4 is an axial cross-sectional view of a second wheel-shaped member carrying corresponding blades according to the present invention;

[0030] Figure 5 is an axial cross-sectional view of the second wheel without the corresponding blade;

[0031] Figure 6 is a longitudinal section view of the blade and blade locking ring. DETAILED DESCRIPTION

[0032] With particular reference to these figures, an apparatus for slitting web material is indicated as a whole by the reference numeral 1 .

[0033] Preferably, the apparatus 1 is provided upstream with means for feeding the web material 2 by unwinding it from a respective reel. The feeding means may comprise, for example, a pair of guide rollers 10,11.

[0034] Preferably, downstream of the rollers 10 , 11 according to the direction in which the coil 2 is unwound, the device is provided with a transverse cutting assembly 100 comprising a first wheel 101 and a second wheel 102 .

[0035] Preferably, the first wheel 101 and the second wheel 102 are arranged side by side on the same working surface and can be operated in a rotatable manner around corresponding parallel rotation axes A, B. Preferably, the first wheel 101 can be operated in a rotatable manner by an actuating device not shown.

[0036] The first wheel 101 has a plurality of opposing blades 103 distributed at a peripheral edge 104 of the first wheel 101 , and the second wheel 102 carries a plurality of blades 105 removably received in corresponding seats 106 distributed at a peripheral edge 107 of the second wheel 102 .

[0037] The first wheel 101 and the second wheel 102 are arranged to define a path between the first wheel 101 and the second wheel 102 , wherein the path is suitable for guiding the web roll-up element 2 .

[0038] In particular, the first wheel 101 and the second wheel 102 are adapted to engage the web material 2 which is fed between the opposing blades 103 and 105 in operation to punch a plurality of transverse cuts 400 at the longitudinal edges 401 of the web material 2 .

[0039] Preferably, the first wheel 101 and the second wheel 102 are mounted in a coaxial manner to a corresponding cylinder (not shown) so as to be adapted to support the entire width of the web material 2 during operation. On the other hand, the width of the first wheel and the second wheel is smaller than the width of the web material 2 and is substantially equal to the depth of the transverse cut 400 to be punched out (see Figure 2 and Figure 4 ). For example, the depth of the transverse cut 400 may be 4 mm.

[0040] According to the invention, the device 1 provides, downstream of the transverse cutting assembly 100 , a longitudinal cutting assembly 200 comprising a guide roller 201 rotatable about a respective axis C, a first cutting member 202 and a second cutting member 203 located downstream of the first cutting member 202 .

[0041] The guide roller 201, the first cutting member 202 and the second cutting member 203 are arranged to define a path between them, in which the web piece 2 is adapted to be guided when it leaves the transverse cutting assembly 100. It should be noted that the longitudinal cutting assembly 200 can be associated with the transverse cutting assembly 100, but the longitudinal cutting assembly 200 can also be used independently of the transverse cutting unit 100, for example to process the web piece 2 that is already provided with a transverse cut.

[0042] In particular, the first cutting member 202 and the second cutting member 203 can be operated independently of each other to move closer to or away from each other between a first non-activated position and a second activated position, in which the first cutting member 202 and the second cutting member 203 are away from the web material 2, and in the second activated position, the first cutting member 202 and the second cutting member 203 are suitable for engaging with the web material 2 fed between the guide roller 201 and the first cutting member 202 and between the guide roller 201 and the second cutting member 203 during operation to punch out a longitudinal cut 402 between the transverse cuts 400 in the same web material 2.

[0043] according to Figure 1 In the preferred embodiment shown, the first cutting member 202 is formed by a circular blade, and the first cutting member 202 can rotate around the corresponding axis D. The second cutting member 203 is formed by a circular arc segment blade, and the second cutting member 203 can rotate around the corresponding axis E.

[0044] In particular, the blade of the second cutting member 203 has a cutting edge formed between two ends forming respective corners on said cutting edge, so that the cut produced by the second cutting member 203 produces respective discontinuities at said ends.

[0045] Preferably, the first and second cutting members 202, 203 are provided at the ends of respective arms 204, 205, which arms are operable in a tilting movement by suitable actuation means (not shown).

[0046] In particular, if Figure 2 As shown, preferably, the transverse cut 400 punched out by the cutting assembly 100 is substantially orthogonal to the longitudinal axis L of the web material 2 , or is inclined relative to the longitudinal axis L.

[0047] according to Figure 3 In the preferred embodiment of the cutting assembly 100 shown, in operation, each corresponding seat 106 accommodating each blade 105 is radially formed in the peripheral edge 107 of the second wheel-shaped member 102, thereby defining at least one cutting edge 500 of the blade 105 protruding from the corresponding seat 106.

[0048] In more detail, Figure 3 As shown, each seating portion 106 includes a first flat surface 300, which is adapted to receive in abutment a corresponding flat surface 501 of a corresponding blade 105. Each seating portion 106 also includes a second flat surface 301 opposite to the first flat surface 300, a bottom wall 305, and a flexible attachment 302 extending between the blade 105 and the second flat surface 301.

[0049] In the illustrated embodiment, the flexible appendage 302 extends radially between the peripheral edge 107 and a mid-portion of the seating portion 106 .

[0050] The flexible attachment 302 and the second flat surface 301 are preferably provided with respective end edges 303, 304 of increased thickness.

[0051] In essence, each seat 106 forms a pocket adapted to receive and house a corresponding blade 105. The length of the pocket 106 is shorter than the length of the blade 105, so that a portion of the blade 105 protrudes from the pocket 106 when the blade 106 is inserted until the blade contacts the bottom wall 305 of the pocket 106.

[0052] Each seat 106 is made of a flexible material with elasticity, such as rubber. Therefore, the flexible attachment 302 can apply compressive stress to the blade 105 in the radial direction during operation.

[0053] Furthermore, the blade 105 has freedom of movement in the radial direction due to the flexibility of the appendage 302. In essence, the blade 105 can move in the radial direction until the flexible appendage 302 comes into contact with the end edge 304 of the second flat surface 301.

[0054] Each opposing blade 103 carried by the peripheral edge 104 of the first wheel 101 comprises a top portion 600 extending in radial direction and capable of cooperating with the cutting edge 500 of the corresponding blade 105 to punch out a corresponding transverse cut 400 at the longitudinal edge 401 of the web material 2 which is fed between the blade 105 and the opposing blade 103 in operation.

[0055] Each opposing blade 103 is made of a resilient flexible material, such as rubber.

[0056] In more detail, the top 600 of each opposing blade 103 is provided with a corresponding inclined wall, which can guide the blade 105 to accurately punch out the cutout 400 due to the freedom of movement of the blade 105 in the radial direction.

[0057] According to a preferred embodiment (see in particular Figure 4 , Figure 5 , Figure 6 ), each blade 105 is formed by a rectangular plate, and one end of the rectangular plate carries the aforementioned cutting edge 500. Specifically, the width of the rectangular plate 105 is equal to the width of the second wheel-shaped member 102.

[0058] In more detail, the rectangular plate 105 has a pair of notches 502, 503 along the side orthogonal to the aforementioned cutting edge 500 (see Figure 6 ). The notches 502, 503 are opposite to each other and are adapted to receive respective locking rings 504, 505, which are adapted to lock the rectangular plate 105 in place during operation (see Figure 4 Specifically, the locking rings 504, 505 are adapted to engage in respective circular grooves 506, 507 formed on respective lateral surfaces of the second wheel 102 to engage with the second wheel 102 so that in operation the circular grooves coincide with the notches 502, 503 of the rectangular plate 105, thereby locking the rectangular plate 105 in place on the second roller 102.

[0059] Preferably, the locking rings 504, 505 are elastic rings. The rings 504, 505 are particularly advantageous because they allow all blades 105 to be locked simultaneously in their respective seats 106. Therefore, there is no need to lock each blade 105 individually, and the working time for assembly and replacement of the blades 105 is very short.

[0060] The operation of the apparatus for slitting web material will be readily understood from the following description.

[0061] Preferentially, in an initial phase, the web material 2 is fed to the transverse cutting assembly 100 by the feeding devices 10, 11. The first wheel 101 and the second wheel 102 of the transverse cutting assembly 100 rotate oppositely about their respective axes A, B.

[0062] The web material 2 is driven forward between the wheels 101, 102 and engages between the opposing blades 103 of the first wheel 101 and the blades 105 of the second wheel 102. By means of the blades 105 and 103, a series of transverse cuts 400 are thus formed at the longitudinal edges 401 of the web material 2.

[0063] Preferably, the web material 2 exiting from the transverse cutting assembly 100 is fed directly to the longitudinal cutting assembly 200. The guide rollers 201 are rotatably operated about respective axes C and the web material 2 is guided between the guide rollers 201 and the first cutting member 202 and the guide rollers 201 and the second cutting member 203 in advance.

[0064] Subsequently, when it is necessary to punch out a longitudinal cut 402 between the previously punched transverse cuts 400 to remove a longitudinal portion 403 of the web material (see Figure 2 ), the first cutting member 202 is operated in an approaching motion and moves from a first inactive position to a second active position, in which the first cutting member 202 is spaced apart from the web material 2. At the same time, the first cutting member 202 rotates about the corresponding axis D. In the second active position, the first cutting member 202 engages the running web material 2 between the guide roller 201 and the same first cutting member 202, so as to punch out a longitudinal cut 402 by a circular blade equipped with the first cutting member 202, thereby removing a longitudinal portion 403 of the web material 2 between the above-mentioned transverse cuts 400.

[0065] After the longitudinal cut is performed, the first cutting member 202 is moved away and returned from the second activated position to the first inactivated position.

[0066] In an appropriate phase relationship, the second cutting member 203 is operated in an approaching movement from a first inactive position, in which the second cutting member 203 is away from the web material 2, to a second active position.

[0067] At the same time, the second cutting member 203 rotates about the respective axis E. In the second activated position, the second cutting member 203 engages the web material 2 running between the guide roller 201 and the same second cutting member 203 to longitudinally trim the edges of said longitudinal cuts 402 previously punched out.

[0068] When the trim cut is performed, the second cutting member 203 is moved away and returned from the second activated position to the first inactivated position.

[0069] In particular, the trimming cut of the edge is necessary because, when the web material 2 is advanced at high speed, the movement time of the first cutting member 202 between the first inactive position and the second active position does not allow a clean and precise cutting of the end edge of the longitudinal cut by the first cutting member 202. In fact, during the movement of the first cutting member 202 between the above-mentioned first position and the second position, the web material continues to advance in the longitudinal direction.

[0070] Advantageously, according to the present invention, the second cutting member 203 operates in the second enabled position in a phase relationship in which the second cutting member 203 engages the edge to be trimmed of the previously punched longitudinal cut 402 with the end portion of the corresponding cutting edge, thereby causing the discontinuity in the cutting portion produced at the end of the cutting edge to be located at the edge of the longitudinal cut.

[0071] It should be noted that the combination of the first and second cutting members 202 , 203 for punching out the longitudinal cutout 402 is particularly advantageous.

[0072] In fact, continuous cutting is possible with only one first cutting member 202, which can be operated towards and away from the web material to be processed, so that cuts of different lengths can be made as required (e.g. by appropriately modifying the time during which the cutting member is in the active position). However, it is not possible to obtain a very precise cut, in particular at the initial and final edges of the cut, because, as previously mentioned, the web element continues to advance during the movement of the cutting member from the active position to the inactive position and vice versa. Therefore, due to the considerable thickness of the web element, a clean and precise cut of the cut edge can only be obtained if the movement stroke of the cutting element from the active position to the inactive position and vice versa is carried out at a very high speed, theoretically infinite speed.

[0073] In contrast, using only the second cutting member 203 capable of discontinuous cutting, the discontinuity of the blade can be used to cleanly and accurately cut the edge of the cut, thereby accurately interrupting the cut when the edges match. However, only a predetermined length of cut can be punched out, which is equal to the length of the portion of the blade between the discontinuous parts. Therefore, each time the length of the cut needs to be changed, the blade needs to be replaced.

[0074] Furthermore, very long cuts require the use of very heavy blades.

[0075] According to the present invention, the combined use of the first cutting member and the second cutting member allows cutting of different lengths to be performed without changing the blade, to use a cutting member of compact size, while obtaining a clean-cut and precise cut.

[0076] This advantageously leads to increased flexibility of use and reduced equipment costs.

[0077] The method and the device according to the invention achieve the object of optimally punching out cuts in the longitudinal edges of a web material.

[0078] In particular, the method and the device for punching cuts in the longitudinal edges of a web material according to the invention make it possible to ensure high operating speeds, thereby operating efficiently even in the case of machines configured to run at very high speeds.

[0079] The device described by way of example can be subjected to numerous modifications and variations according to different requirements.

[0080] In the actual implementation of the present invention, the materials used as well as the shapes and sizes can be modified as needed.

[0081] If the technical features mentioned in any claims are followed by reference numerals, these reference numerals are only used to enhance the understanding of the claims, and thus these reference numerals should not be construed in any way to limit the scope of each element identified by these reference numerals for illustrative purposes.

Claims

1. A device for cutting a web material (2), characterized in that The device comprises a longitudinal cutting assembly (200), the longitudinal cutting assembly (200) comprising a guide roller (201), a first cutting member (202), and a second cutting member (203), the guide roller (201) being rotatable around a corresponding axis (C), the second cutting member (203) being located downstream of the first cutting member (202), the first cutting member (202) and the second cutting member (203) being operable independently of each other to move in a manner of approaching or moving away from each other between a first non-activated position and a second activated position, in which the first non-activated position and the second The cutting members (203) are spaced apart from the web material (2) fed in operation between the guide roller (201) and the first cutting member (202) and between the guide roller (201) and the second cutting member (203), respectively, and in the second activated position, the first cutting member (202) and the second cutting member (203) are adapted to engage with the web material (2) between the guide roller (201) and the first cutting member (202) and between the guide roller (201) and the second cutting member (203) to punch out longitudinal cuts (402) in the web material (2).

2. The device according to claim 1, wherein: The first cutting member (202) is formed by a circular blade, and the first cutting member (202) is rotatable about a respective axis (D).

3. The device according to claim 1 or 2, wherein: The second cutting member (203) is formed by a circular arc-shaped blade, and the second cutting member (203) is rotatable around a corresponding axis (E).

4. The device according to any one of the preceding claims, wherein The blade of the second cutting member (203) has a cutting edge extending between two ends forming respective angles on the cutting edge.

5. The device according to any one of the preceding claims, wherein: The first cutting member (202) and the second cutting member (203) are carried at the ends of respective arms (204, 205) which are operable in a tilting movement.

6. A method for punching cuts in a web material (2), wherein: The method comprises the following steps: a. feeding the web material (2) to a longitudinal cutting assembly (200), the longitudinal cutting assembly (200) comprising a guide roller (201), a first cutting member (202) and a second cutting member (203), the guide roller (201) rotating around an axis (C), the second cutting member (203) being located downstream of the first cutting member (202); b. operating the first cutting member (202) so as to move the first cutting member (202) from a first inactive position toward a second active position, in which the first cutting member (202) is spaced apart from the web material (2), and in which the first cutting member (202) is capable of engaging the web material (2) traveling between the guide roller (201) and the first cutting member (202), thereby punching a longitudinal cut (402) on the web material (2); c. operating the first cutting member (202) so that the first cutting member (202) moves from the second enabled position to the first disabled position, and moving the second cutting member (203) from the first disabled position in a close manner toward the second enabled position in an appropriate phase relationship, wherein the second cutting member (203) is spaced apart from the web material (2) in the first disabled position, and wherein the second cutting member (203) is capable of engaging with the web material (2) running between the guide roller (201) and the second cutting member (203), thereby punching out a longitudinal cut to trim the boundary of the previously punched longitudinal cut (402); d. Moving the second cutting member (203) away from the second activated position to the first inactivated position.

7. The method according to claim 6, wherein: The first cutting member (202) is formed by a circular blade, and the first cutting member (202) rotates around a corresponding axis (D); The second cutting member (203) is formed by an arc-shaped blade, and the second cutting member (203) rotates around the corresponding axis (E); wherein, in the step e, the second cutting member (203) works in the second enabled position in the following phase relationship: the phase relationship enables the second cutting member (203) to engage the edge to be trimmed of the previously punched longitudinal cut (402) with the end portion of the corresponding cutting edge.

8. The method according to claim 6 or 7, wherein: The approaching movement or the moving away movement is a tilting movement.

9. The method according to any one of claims 6 to 8, wherein: The web material (2) fed to the longitudinal cutting assembly (200) is provided with a plurality of transverse cuts (400) at the longitudinal edges (401) of the web material (2), such that one longitudinal cut (402) removes a longitudinal portion of the web material (2) located between the transverse cuts (400).

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