Sheet cutting device and sheet cutting method

Abstract

To provide a sheet cutting device capable of cutting sheets stably and accurately while suppressing the influence of tension fluctuations and the like applied on a sheet wound in a roll shape.SOLUTION: A sheet cutting device 1 comprises a supply unit 10, a cutting unit 30, and a clamping unit 40. The cutting unit 30 includes a guide rail 330 formed with a groove, a linear shaft 310, and a cutter arm fixed in a movable manner. The cutter arm has a first clamp adjustment member 53 and is movable in a first direction in a state where the cutter blade 55 is inserted to the groove. The clamping unit 40 includes a clamp piece 430 capable of clamping the sheet, a second clamp adjustment member 60, and a lifting part 440 for fixing these components in a vertically-movable manner. When the cutter arm is within a predetermined range, the sheet is clamped. When the cutter arm is outside the predetermined range, the first clamp adjustment member 53 pushes up the second clamp adjustment member 60 to release clamping of the sheet.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an apparatus for unwinding a rolled sheet by a predetermined length and cutting it in the width direction. [Background technology]

[0002] For packaging products, packaging sheets such as air caps with specified vertical and horizontal dimensions are sometimes used. Such packaging sheets are usually purchased in a rolled form, and the required amount is pulled out appropriately, and cut in the width direction with a cutter knife or the like to the specified length. However, this method requires the repeated and cumbersome work of measuring the length, applying a ruler, and cutting with a cutter knife, and the work time and dimensional accuracy of the sheet depend on the skill of the worker. Another method is to wrap the packaging sheet around a plate material with specified vertical and horizontal dimensions in multiple layers, and then move a cutter knife along two sides of the plate material to create multiple sheets at once. However, when the sheet has a certain thickness like air caps, the sheet dimensions of the outer wrap tend to be larger than the sheet dimensions of the inner wrap, and there is a problem that the sheet dimensions cannot be accurately obtained.

[0003] On the other hand, Patent Document 1 describes a sheet cutting device that includes a supply unit that rotatably supports a roll-shaped sheet and a cutting unit that cuts the sheet along the width direction. Here, the cutting unit includes a cutter unit including a cutter blade and a cutter blade holding unit that holds the cutter blade, a shaft, and a guide rail. The shaft supports the cutter unit so that it can slide in the axial direction and rotate around the axis, and the guide rail is provided at a predetermined distance from the shaft, has a groove along the axial direction, and is supported so that it can rotate around the axis of the shaft. In this sheet cutting device, when the cutter unit is slid along the axial direction of the shaft, the cutter blade moves in parallel while being inserted into the groove of the guide rail, thereby cutting the sheet placed on the guide rail in the width direction. In addition, when the cutter unit is not used, the cutter unit and the guide rail can be rotated around the axis of the shaft while the cutter unit is sandwiched between the shaft and the guide rail to retract it. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2023-64239 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the cutter unit can slide along the axial direction of the shaft, and the cutter blade moves parallel while inserted in the groove of the guide rail, so it is thought that the sheet can be cut relatively accurately to a specified size. However, since the sheet is in a state where it is pulled out from the roll, it is preferable that the sheet can be cut stably and accurately even if there is a fluctuation in the tension applied to the sheet.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and has as its objective the provision of a sheet cutting device and a sheet cutting method that can suppress the effects of fluctuations in tension applied to a rolled-up sheet and cut the sheet stably and accurately. [Means for solving the problem]

[0007] A first configuration of a sheet cutting device according to the present embodiment includes a supply unit that rotatably supports a roll on which a sheet is wound so that the sheet can be unwound from the roll, a cutting unit that cuts the sheet, and a clamping unit that clamps the sheet, the cutting unit including a guide rail having a groove formed along a first direction, a linear shaft that is spaced a predetermined distance from the guide rail and extends along the first direction, and a cutter arm that is fixed to the linear shaft so as to be movable along the first direction and has a cutter blade at its tip, the cutter arm including a first clamp adjustment member that is movable along the first direction with the cutter blade inserted into the groove, The clamp section comprises a clamp piece capable of clamping the sheet placed on the guide rail, a second clamp adjustment member, and a lifting section that fixes the clamp piece and the second clamp adjustment member so that they can be raised and lowered. When the position of the cutter arm along the first direction is within a predetermined range, the first clamp adjustment member does not push up the second clamp adjustment member and the sheet is clamped. When the position of the cutter arm along the first direction is outside the predetermined range, the first clamp adjustment member pushes up the second clamp adjustment member, and the clamp on the sheet is released due to the lifting section lifting the clamp piece and the second clamp adjustment member.

[0008] In a second configuration of a sheet cutting device according to another embodiment of the present invention, in the above-described first configuration, the predetermined range may include at least a range in the width direction in which the sheet exists.

[0009] In addition, a third configuration of a sheet cutting device according to another embodiment of the present invention is such that, in the first or second configuration described above, the cutter arm has blades on both sides along the first direction so that the sheet can be cut in either direction along the first direction when the cutter blade is inserted into the groove.

[0010] In addition, a fourth configuration of a sheet cutting device according to another embodiment of the present invention may be such that, in any of the first to third configurations described above, the second clamp adjustment member is arranged in a symmetrical shape at positions corresponding to one end side and the other end side of the sheet along the first direction.

[0011] In addition, a fifth configuration of a sheet cutting device according to another embodiment of the present invention may be such that, in any of the first to fourth configurations described above, the second clamp adjustment member has an inclined portion whose lower end edge has a predetermined inclination angle and a bottom surface portion that is approximately horizontal, and as it moves outward along the first direction, the position of the lower end edge gradually descends due to the inclined portion, with the position being the lowest at the bottom surface portion.

[0012] In addition, a sixth configuration of a sheet cutting device according to another embodiment of the present invention may be the fifth configuration described above, wherein the edge of the lower end of the bottom surface portion has an upward inclination of 5° or more and 10° or less with respect to the horizontal as it moves outward along the first direction.

[0013] In addition, a seventh configuration of a sheet cutting device according to another form of the present embodiment may be such that, in the above-mentioned fifth or sixth configuration, the second clamp adjustment member has a shape having a protrusion that protrudes locally downward at the boundary between the inclined portion of the lower end edge and the bottom surface portion.

[0014] An eighth configuration of the sheet cutting method according to this embodiment includes the steps of rotatably supporting a roll on which the sheet is wound so that the sheet can be unwound from the roll, unwinding a predetermined length of the sheet from the roll, determining a cutting position of the sheet with the position of the cutter arm along the first direction outside a predetermined range and the clamp on the sheet open, cutting the sheet along the first direction while the sheet is clamped by sequentially moving the position of the cutter arm along the first direction from outside the predetermined range to within the predetermined range, and moving the cutter arm until cutting is completed and the position of the cutter arm along the first direction is outside the predetermined range, and the clamp on the sheet is open. Effect of the Invention

[0015] According to the present embodiment, it is possible to provide a sheet cutting device and a sheet cutting method that can suppress the effects of fluctuations in tension applied to a rolled sheet and cut the sheet stably and accurately. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic perspective view illustrating an example of a sheet cutting device according to an embodiment of the present disclosure. [Diagram 2] 4 is a side view illustrating the configuration of a cutting unit of the sheet cutting device as viewed from the +X direction. FIG. [Diagram 3] 4 is a side view illustrating the configuration of a cutting unit of the sheet cutting device as viewed from the +X direction. FIG. [Figure 4] 4 is a side view illustrating the configuration of a cutting unit of the sheet cutting device as viewed from the +X direction. FIG. [Diagram 5] 13 is a side view illustrating the configuration of the cutter unit as viewed from the +X direction. FIG. [Figure 6] FIG. 11 is a side view illustrating the configuration of the dog as viewed from the +X direction. [Figure 7] FIG. 11 is a side view illustrating the configuration of the dog as viewed from the +X direction. [Figure 8]10 is a front view seen from the -Y direction for explaining an example of a sheet cutting method by the sheet cutting device. FIG. [Figure 9] FIG. 4 is a flow chart illustrating an example of a sheet cutting method by the sheet cutting device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an example of a sheet cutting device and a sheet cutting method according to the present disclosure will be described with reference to the drawings, etc. However, the sheet cutting device and the sheet cutting method according to the present disclosure are not limited to the device and the method according to the embodiment described below.

[0018] The figures shown below are schematic. Therefore, the size, shape, thickness of each layer in the cross-sectional view, etc. are appropriately exaggerated to facilitate understanding. In addition, hatching showing the cross section of the member is appropriately omitted in each figure. The numerical values ​​of the dimensions and material names of each member described in this specification are examples of embodiments, and are not limited to these and can be appropriately selected and used. In this specification, terms that specify the shape or geometric conditions, such as parallel, orthogonal, and vertical, are intended to include substantially the same state in addition to their strict meaning. In addition, for convenience of explanation, the terms "upper" or "lower" may be used in the description relative to the paper, but the up-down direction may be reversed, and the same applies to the left-right direction.

[0019] 1. Embodiments of the present disclosure A typical embodiment of the sheet cutting device of the present disclosure will be described. Here, for convenience of describing the sheet cutting device 1, an XYZ coordinate system is provided. In the sheet cutting device 1, a Y axis is provided along the axial direction of the roll 500 on which the sheet 510 is wound, and a Z axis is provided along the vertical direction. In addition, an X axis perpendicular to the Y axis and the Z axis is provided. With respect to the X axis, the direction in which the sheet 510 is conveyed from the roll 500 from the back side to the front side is the +X direction side, and the opposite direction is the -X direction side. In addition, when the +X direction is viewed to the right, the direction toward the front side is the -Y direction side, the opposite direction is the +Y direction side, the vertical upward direction is the +Z direction side, and the vertical downward direction is the -Z direction side.

[0020] The sheet cutting device 1 is, for example, a device for cutting a long sheet wound in a roll shape for use in packaging, etc., in the width direction to the required length while appropriately unwinding the sheet. The sheet includes any thin film or thick sheet made of resin, paper, metal, etc., used for packaging, etc., but typically the sheet can be an air cap for packaging products to protect them from external impact. Such a sheet 510 is wound as a roll 500. As shown in FIG. 1, the roll 500 is supported rotatably by passing a roll shaft 12 that connects a pair of shaft support frames, a first shaft support frame 11a and a second shaft support frame 11b, of the supply unit 10 through the axis. Therefore, the sheet 510 can be easily unwound from the roll 500 by simply pulling the tip of the sheet 510 by hand.

[0021] The sheet cutting device 1 also includes a cutting unit 30 that is disposed downstream of the supply unit 10 and cuts the sheet 510, which has been fed out by a predetermined length, in the width direction. The sheet 510 fed out from the roll 500 by the supply unit 10 is finally redirected to the horizontal +X direction by a first guide frame 13 located slightly diagonally above the +X direction side of the roll 500 and a second guide frame 14 located below the first guide frame 13. The sheet is then conveyed to the cutting unit 30 and the clamp unit 40.

[0022] The cutting unit 30 has a main function of cutting the sheet 510, and the clamping unit 40 has a main function of clamping the sheet 510 so as to prevent the sheet 510 from shifting position while the cutting unit 30 cuts the sheet 510. The worker can manually pull out the required amount of sheet 510 from the roll 500 in the +X direction while referring to the tape measure 220 or the like.

[0023] The cutting unit 30 has a guide rail 330 in which a slit 330a is formed as a groove along a first direction parallel to the Y-axis, which is the width direction of the sheet 510, and a linear shaft 310 that is spaced a predetermined distance upward from the guide rail 330 and extends along the first direction. The cutting unit 30 also has a cutter arm 54 that is fixed to the linear shaft 310 so as to be movable along the first direction and has a cutter blade 55 at its tip. The cutter arm 54 has an idler 53, such as a pulley, as a first clamp adjustment member, and is movable along the first direction with the cutter blade 55 inserted into the slit 330a. The first clamp adjustment member is not limited to a pulley, and may be a plate-shaped or block-shaped part. The first clamp adjustment member may have a function of raising and lowering the second clamp adjustment member and the clamp piece in combination with a second clamp adjustment member described later.

[0024] The clamping unit 40 has a clamper 430 capable of clamping the sheet 510 placed on the guide rail 330 without interfering with the cutter arm 54, and a dog 60 which is a second clamp adjustment member. The clamper 430 is a type of clamp piece having a function of clamping the sheet 510 placed on the guide rail 330, and the clamp piece is not limited to a plate-like member substantially parallel to the guide rail 330 like the clamper 430. The clamp piece may be a rubber-like member or a sponge-like member of any shape, and may be configured to hold down the sheet 510 while adsorbing it with a suction cup-like part. The dog 60 is a plate-like member and can be engaged with the above-mentioned idler 53 according to their mutual positional relationship along the first direction, and the entire clamper 430 and the dog 60 can be displaced in the vertical direction depending on the state of engagement between the two and the shape of the dog 60. In this way, the clamping unit 40 has a lifting unit 440 which fixes the entire clamper 430 and the dog 60 so that they can be lifted and lowered. The second clamp adjustment member is also not limited to the dog 60, and may be a block-shaped part. The second clamp adjustment member may have a function of combining with the first clamp adjustment member and raising and lowering the clamp piece in response to the raising and lowering of the second clamp adjustment member.

[0025] Here, when the position of the cutter arm 54 along the first direction is within a predetermined range in which the sheet 510 is cut, the idler 53, which is the first clamp adjustment member, does not push up the dog 60, which is the second clamp adjustment member. Then, the clamper 430 and the dog 60 are not raised as a whole by the lifting unit 440, and the sheet 510 is clamped. Therefore, when the position of the sheet 510 is within the predetermined range in which the sheet 510 is cut, even if there is a tension fluctuation in the sheet 510, the sheet 510 is prevented from shifting its position during cutting. The predetermined range can be any range of the cutter arm 54 along the first direction, but it is preferable that the predetermined range includes at least the width direction range in which the sheet 510 is arranged. This is because the clamper 430 is lowered to the lower end in the predetermined range, and the sheet 510 present within that range can be effectively clamped.

[0026] On the other hand, when the position of the cutter arm 54 along the first direction is outside the predetermined range, the idler 53 pushes up the dog 60, and the clamper 430 and the dog 60 are raised as a whole by the lifting unit 440, thereby releasing the clamp on the sheet 510. Therefore, when the sheet 510 is outside the predetermined range that is outside the range for cutting the sheet 510, the clamp on the sheet 510 by the clamper 430 is released, so that the sheet 510 is quickly moved after cutting is completed, and preparation for cutting the next sheet 510 is advanced. As a result, according to the embodiment of the present disclosure, it is possible to provide a sheet cutting device and a sheet cutting method that can stably and accurately cut a sheet by suppressing the influence of fluctuations in tension applied to a rolled sheet. The configuration of each part of the sheet cutting device 1 will be described in detail below.

[0027] [a] Configuration of sheet cutting device [i] Supply section As shown in Fig. 1, the supply unit 10 is composed of a pair of shaft support frames 11 that support both ends of a cylindrical roll shaft 12 that is fitted along the axis of the target roll 500. The shaft support frames 11 are composed of a first shaft support frame 11a that supports the end of the roll shaft 12 on the -Y direction side, and a second shaft support frame 11b that supports the end of the roll shaft 12 on the +Y direction side. At least one end of the roll shaft 12 is detachably attached to the shaft support frame 11, and by separating one of the ends of the roll shaft 12 from the shaft support frame 11, the roll shaft 12 can be easily fitted into the shaft hole of the roll 500.

[0028] However, the supply unit 10 is not limited to one that supports the roll 500 by the roll shaft 12 inserted into the shaft hole, but may be one that supports the roll 500 from below by a plurality of freely rotating rollers. Also, a structure in which both ends of the roll shaft 12 are rotatably chucked from the side may be used.

[0029] The roll 500 thus fixed to the supply section 10 is rotatable about the roll shaft 12, so that the sheet 510 can be easily pulled out by pulling it by hand.

[0030] The supply unit 10 first guides the sheet 510 unwound from the roll 500 attached to the roll shaft 12 upward. Thereafter, the supply unit 10 further includes two guide frames for guiding the sheet 510 to the lower end: a first guide frame 13 arranged on the upper side and a second guide frame 14 arranged on the lower end side. The first guide frame 13 is a shaft having a cylindrical cross section, and the second guide frame 14 is a plate material having a rectangular cross section. The first guide frame 13 is designed to give as little friction as possible to the suspended sheet 510 so that the worker can easily pull out the sheet 510, and the second guide frame 14 is designed to give appropriate friction to the sheet 510 and generate appropriate tension.

[0031] The sheet 510 pulled out from the roll 500 is first lifted upward by the first guide frame 13 in order to prevent the tension from fluctuating due to a change in the angle at which the sheet 510 enters the second guide frame 14, which would occur due to a change in the diameter of the roll 500.

[0032] [ii] Cutting section As shown in Fig. 1, the cutting unit 30 is disposed on the +X direction side downstream of the supply unit 10, and has a function of cutting the fed sheet 510 to a predetermined length along the width direction. Figs. 2 to 4 are side views of only the cutting unit 30 and the clamp unit 40 of the sheet cutting device 1, as viewed from the +X direction, for explaining the configurations and operations of the relevant parts. Fig. 2(a) is a view of only the cutting unit 30.

[0033] As shown in FIG. 2(a), the cutting unit 30 has a guide rail 330 in which a slit 330a is formed as a groove along a first direction parallel to the Y-axis, which is the width direction of the sheet 510, and a linear shaft 310 that is spaced apart from the guide rail 330 by a predetermined distance and extends along the first direction. The "predetermined distance" merely indicates that the guide rail 330 and the linear shaft 310 are spaced apart from each other by a substantially constant distance in parallel, and actually indicates a distance that is the length of the cutter arm 54 and the like extending in the vertical direction. The "predetermined distance" is not strictly limited to the guide rail 330 and the linear shaft 310 being parallel to each other and spaced apart by a constant distance. The predetermined distance may be set to a distance that allows the cutter arm 54 to smoothly slide the linear shaft 310 along the Y-axis direction with the cutter blade 55 inserted into the slit 330a of the guide rail 330. For example, the variation in the distance between the guide rail 330 and the linear shaft 310 caused when the axis lines of the guide rail 330 and the linear shaft 310 are inclined relative to each other within a range of 0° to 5° is permitted.

[0034] The cutting section 30 also includes a cutter unit 50 that is fixed to the linear shaft 310 so as to be movable along the first direction and has a cutter blade 55 at its tip. The cutter unit 50 includes a cutter arm 54 that extends in the vertical direction from the guide rail 330 to the linear shaft 310, and a cutter blade attached to the lower end of the cutter arm 54. The cutter unit 50 also includes a mounting block 52 attached to the upper end of the cutter arm, and a slider 51 detachably fixed to the mounting block 52.

[0035] The mechanism of the linear shaft 310 and the slider 51 is arbitrary, and may be a so-called linear guide configuration, or may be a configuration in which the slider 51, which has a through hole with a circular cross section, slides along the linear shaft 310, which has a circular cross section. The operator can easily slide the entire cutter unit 50 by gripping the cutter arm 54 and moving it in the horizontal direction along the Y axis. For example, in FIG. 2(a), the operator grips the cutter arm 54 of the cutter unit 50, which is initially positioned at the left end as indicated by the dashed line, and moves it in the +Y direction. As a result, the cutter unit 50 moves to the right end indicated by the solid line. It goes without saying that the operator can grip the cutter arm 54 and move it in the -Y direction to move the cutter unit 50 to the original left end indicated by the dashed line.

[0036] In addition, an idler 53 capable of engaging with a dog 60 of the clamp unit 40 described later is attached near the upper end of the mounting block 52 of the cutter unit 50. In this embodiment, the idler 53 is a freely rotatable pulley having a groove formed along the outer periphery of a disk-shaped part, but is not limited thereto. The idler 53 may be a simple protruding part as long as it is capable of pushing the dog 60 upward according to the position of the cutter unit 50. Since the idler 53 is a pulley having a groove formed along the outer periphery of the disk-shaped part, the dog 60, which is a plate-shaped member, and the outer periphery groove of the idler 53 engage with each other, effectively preventing the dog 60 from shifting in its thickness direction and coming off the idler 53.

[0037] In this embodiment, the pulley constituting the idler 53 is provided at two locations along the Y-axis, which is the moving direction of the cutter unit 50. The number of pulleys is not limited to two, and may be one or three or more. By providing two or more pulleys instead of one, the lifting and lowering operation of the clamper 430 can be appropriately adjusted even if the size of the dog 60 is reduced, as described below. Note that the above-described configuration of the cutter unit 50 is merely one example shown in this embodiment, and the cutter arm 54 may also function as the mounting block 52 and the slider 51, and may be provided with a cutter blade 55 at the lower end of the cutter arm 54 and an idler 53 at the upper end.

[0038] As shown in FIG. 2(a), both left and right ends of the guide rail 330 are supported and fixed by a pair of base frames 15, a first base frame 15a on the -Y direction side and a second base frame 15b on the +Y direction side. Both left and right ends of the linear shaft 310 are supported and fixed by a pair of support shafts 320, a first support shaft 320a and a second support shaft 320b, which protrude upward from the pair of base frames 15. The upper ends of the first support shaft 320a and the second support shaft 320b form a protruding portion 320c that protrudes further upward than the position of the linear shaft 310. As described later, the lifting portion 440 of the clamp unit 40 is fitted into the protruding portion 320c.

[0039] FIG. 5 is a side view of the cutter unit 50, seen from the +X direction, for explaining the configuration of the cutter blade 55 and its vicinity. The cutter blade 55 has a first blade 55p facing the -Y direction side and a second blade 55q facing the +Y direction side as a cutting edge 55a. The cutter blade 55 has such a configuration, so that the cutter unit 50 can appropriately cut the sheet 510 both when it slides from the -Y direction side to the +Y direction side of the set sheet 510 and when it slides from the +Y direction side to the -Y direction side. The cutter arm 54 has blades on both sides along the first direction so that the sheet 510 can be cut in either one or the other direction along the first direction parallel to the Y axis when the cutter blade 55 is inserted into the slit 330a of the guide rail 330.

[0040] Furthermore, by forming a substantially square-shaped portion with vertices projecting to the left and right above the cutting edge 55a of the cutter blade 55, the risk of an operator accidentally inserting a finger near the cutting edge 55a can be reduced. The entire cutter blade 55 or the cutting edge 55a may be configured to be detachable from the cutter arm 54 or the main body of the cutter blade 55. In this case, only the cutting edge 55a can be easily replaced, improving workability.

[0041] [iii] Clamp section As shown in Fig. 1, the clamp unit 40 is disposed near the cutting unit 30 on the +X direction side downstream of the supply unit 10. The clamp unit 40 has a function of stably clamping the sheet 510 while the cutting unit 30 cuts the fed sheet 510 in the width direction to a predetermined length, and quickly releasing the clamp on the sheet 510 after cutting is completed. This enables the sheet cutting device 1 to perform a stable and efficient cutting operation of the sheet 510. For reference, the clamp unit 40 is hatched in Fig. 1 and Figs. 2 to 4 to distinguish it from the cutting unit 30.

[0042] As shown in FIG. 2(b) and other figures, the clamping unit 40 includes a linear shaft 410 extending substantially parallel to the linear shaft 310 of the cutting unit 30, and a pair of support shafts 420 fixed to both ends of the linear shaft 410 and extending in the vertical direction. The clamping unit 40 further includes a pair of clampers 430 provided at the lower end of the support shaft 420 for pressing both ends of the sheet 510 against the guide rails 330 to clamp the sheet. Note that, in this embodiment, the linear shafts 310 and 410 each refer to a cylindrical portion having a circular cross section, but it goes without saying that one or both of these may be a square pillar or a plate material.

[0043] A first support shaft 420a is fixed to the end of the linear shaft 410 on the -Y direction side, and a first clamper 430a, which is a plate-shaped member with an arrangement direction substantially parallel to the arrangement direction of the guide rail 330, is fixed to the lower end of the first support shaft 420a. Similarly, a second support shaft 420b is fixed to the end of the linear shaft 410 on the +Y direction side, and a second clamper 430b, which is a plate-shaped member with an arrangement direction substantially parallel to the arrangement direction of the guide rail 330, is fixed to the lower end of the second support shaft 420b.

[0044] Furthermore, a first lifting section 440a and a second lifting section 440b protrude from the first support shaft 420a and the second support shaft 420b, respectively, as the lifting section 440. The first lifting section 440a and the second lifting section 440b are configured to be fitted to the upper end protrusions 320c of the first support shaft 320a and the second support shaft 320b of the cutting section 30 so as to be movable up and down. That is, the linear shaft 410, the pair of support shafts 420, the pair of clampers 430, and the pair of lifting sections 440 that integrally constitute the clamping section 40 are supported by the pair of support shafts 320 of the cutting section 30 in a state in which the entirety of them can move up and down.

[0045] Although the pair of lifting parts 440 are described as being configured to be liftably fitted to the protruding parts 320c at the upper ends of the pair of support shafts 320 of the cutting unit 30, the configuration of the lifting parts is not limited thereto. For example, the lifting parts 440 and the support shafts 320 may be configured to be slidable like a so-called linear guide.

[0046] The clamper 430 can move upward away from the guide rail 330 or come into contact with the guide rail 330 to press down the sheet 510 depending on the elevation state of the elevation unit 440. However, regardless of the position of the clamper 430, the relative positional relationship between the clamper 430 and the cutter unit 50 is taken into consideration so that the clamper 430 does not interfere with the cutter unit 50. This allows the cutter unit 50 to cut the sheet 510 and the clamper 430 to clamp and release the sheet 510 to be performed independently without interfering with each other.

[0047] Further, a pair of dogs 60 is provided near the left and right ends of the linear shaft 410, with a first dog 60a on the -Y direction side and a second dog 60b on the +Y direction side. The dog 60 is also referred to as a second clamp adjustment member. Details of the shape of the dog 60 will be described later, but as shown in FIG. 2(b), when the cutter unit 50 is closest to the -Y direction side, that is, when the cutter unit 50 is at position L1, the lifting section 440 is positioned at the highest position.

[0048] This is because the shape of the first dog 60a when viewed from above in the +X direction is formed such that the edge of the lower end of the first dog 60a gradually descends downward as it approaches the -Y direction. Therefore, the first dog 60a, which meshes with and comes into contact with the idler 53 of the cutter unit 50, is lifted relatively upward, and the lifting part 440 rises. As a result, the pair of clampers 430 also rise and move away from the guide rail 330.

[0049] 2(c), when the cutter unit 50 reaches position L2, which is slightly moved in the +Y direction from position L1, the lifting part 440 is displaced from the highest position to a position slightly lowered. Here, the idler 53 abuts against the first dog 60a at a midpoint of the slope of the portion formed so that the edge of the lower end of the first dog 60a gradually descends downward. Therefore, the first dog 60a, which abuts while engaging with the idler 53 of the cutter unit 50, descends relatively lower than when it was at position L1, and the lifting part 440 descends by that amount. As a result, the pair of clampers 430 maintain a state of being spaced apart from the guide rail 330, but the distance between them is reduced.

[0050] Next, as shown in FIG. 3(a), when the cutter unit 50 reaches position L3, which is further moved in the +Y direction side than position L2, the lifting part 440 is disposed in a position lowered to the lower end. Here, the idler 53 passes the upper end part of the inclination of the part formed so that the edge of the lower end of the first dog 60a gradually descends downward, and separates from the first dog 60a. Therefore, the upward lifting force by the idler 53 of the cutter unit 50 no longer acts, and the entire clamp part 40 descends by its own weight, so that the lifting part 440 descends to the lower end position. As a result, the pair of clampers 430 abut against the sheet 510 arranged on the guide rail 330 and act to press it against the guide rail 330.

[0051] For this reason, if the positional relationship of the cutting section 30 and the clamp section 40 is set so that the sheet 510 is cut when the cutter unit 50 moves from position L3 toward the +Y direction, the following occurs. That is, while the cutter unit 50 is cutting the sheet 510, both ends of the sheet 510 are always appropriately clamped by the clamper 430 of the clamp section 40, so that deterioration of the cutting accuracy due to misalignment of the sheet 510 during cutting can be suppressed. In addition, when the cutter unit 50 moves from position L3 toward the -Y direction, the clamper 430 rises and the clamp on the sheet 510 is released, so that preparations such as pulling out the sheet 510 and adjusting its position can be made quickly, improving workability.

[0052] 3(b), until the cutter unit 50 reaches position L4, which is further moved in the +Y direction from position L3, the lifting section 440 is disposed in a position lowered to the lower end, similar to when the cutter unit 50 is at position L3. Therefore, if the cutter unit 50 is set to cut the sheet 510 between positions L3 and L4, the pair of clampers 430 stably contact the sheet 510 placed on the guide rail 330 during this period, and continue to press the sheet 510 against the guide rail 330.

[0053] 4(a), when the cutter unit 50 reaches position L5, which is slightly moved in the +Y direction from position L4, the lifting section 440 is positioned at a position slightly elevated from the lowest position. Here, the shape of the second dog 60b when viewed in a plan view from the +X direction is formed symmetrically with respect to the first dog 60a, and the shape is formed such that the edge of the lower end of the second dog 60b gradually descends downward as it approaches the +Y direction.

[0054] At this time, the idler 53 abuts against the second dog 60b at a midpoint of the slope of the portion formed so that the edge of the lower end of the second dog 60b gradually descends downward. Therefore, the second dog 60b that abuts while meshing with the idler 53 of the cutter unit 50 rises relatively higher than when it was at position L4, and the lifting part 440 rises by that amount. As a result, the pair of clampers 430 are separated from the guide rail 330 by a slight distance.

[0055] 4B, when the cutter unit 50 reaches position L6, the furthest in the +Y direction, the lifting section 440 is positioned at the highest position. That is, the lifting section 440 and the clamper 430 are in the same state as in position L1, and the pair of clampers 430 are farthest from the guide rail 330.

[0056] Next, the characteristics of the shape of the dog 60, which is the second clamp adjustment member, and its relationship with the idler 53, which is the first clamp adjustment member, will be described. Figures 6 and 7 are enlarged views of the vicinity of the first dog 60a, which is disposed on the -Y direction side, of the dog 60 shown in Figure 2(b) and other figures.

[0057] As shown in FIG. 6(a), the first dog 60a in plan view from the +X direction includes an inclined portion 62 whose lower edge has a predetermined inclination angle, and a bottom surface portion 63 that is substantially horizontal. A fixing portion 61 that is a portion for attaching to the linear shaft 410 is provided at the upper end of the inclined portion 62. In the dog 60 of this embodiment, the inclined portion 62 and the bottom surface portion 63, as well as the inclined portion 62 and the fixing portion 61, are configured as continuous, integrated parts, and are manufactured, for example, by resin molding or cutting out a metal piece. However, the dog 60 may be formed by preparing each part as a separate part and assembling them.

[0058] Here, the edge of the lower end of the inclined portion 62 has an upward inclination with respect to the horizontal as it moves inward along the Y-axis, which is the horizontal direction, toward the +Y direction, which is the inner side. When this inclination angle is θ1, θ1 is preferably 40° or more and 50° or less, and more preferably 43° or more and 47° or less.

[0059] Since θ1 is in the former range, if θ1 is made larger, the clamper 430 can be raised and lowered even if the horizontal movement amount of the cutter unit 50 is small, and a compact device design with a reduced width size of the sheet cutting device 1 can be achieved. Furthermore, if θ1 is made smaller, the load load when the cutter unit 50 moves can be reduced, making it easier to raise and lower the clamper 430. On the other hand, since θ1 is in the latter range, it is possible to achieve both a reduction in the amount of movement of the cutter unit 50 required for raising and lowering the clamper 430 and a reduction in the load load when the cutter unit 50 moves, which is required for raising and lowering the clamper 430. The dog 60 is shaped so that the position of the edge of the lower end gradually descends due to the inclined portion 62 as it moves outward along the first direction parallel to the Y axis, and the position is the lowest at the bottom surface portion 63.

[0060] Furthermore, the edge of the lower end of the bottom surface portion 63 may be formed along the direction along the horizontal Y-axis, but in this embodiment, the edge has a shape that has a slight upward inclination with respect to the horizontal as it moves toward the outer -Y direction side. When this inclination angle is θ2, it is preferable that θ2 is 5° or more and 10° or less. By setting θ2 in this range, it is possible to reduce the risk that the cutter unit 50 will naturally move toward the +Y direction side without the operator intentionally trying to move the cutter unit 50, and that the sheet 510 will be unintentionally cut.

[0061] Furthermore, a protrusion 64 is provided at the boundary between the inclined portion 62 at the edge of the lower end of the first dog 60a and the bottom surface portion 63 disposed on the -Y direction side thereof, and protrudes locally downward from the first dog 60a. The protrusion amount d1 of the protrusion 64 from the straight line along the edge of the lower end of the bottom surface portion 63 is preferably 0.2 mm or more and 0.4 mm or less. The shape of the protrusion 64 when viewed in plan from the +X direction side may be any shape such as a semicircle, an elliptical semicircle, a triangle, a rectangle, a polygon, etc., but is preferably formed with a curved surface such as a semicircle from the viewpoint of reducing the impact upon collision with the idler 53.

[0062] Here, the relationship between the dog 60 and the idler 53 due to the change in the position of the cutter unit 50 will be described with reference to FIG. 6, FIG. 7, etc. First, it is assumed that the cutter unit 50 is at position L1 in FIG. 2(b). At this time, the positional relationship between the first dog 60a and the idler 53 of the cutter unit 50 is as shown in FIG. 6(b). The idler 53, which is a pulley, is provided at two locations along the Y-axis direction at the upper end of the mounting block 52 of the cutter unit 50, with the first idler 53a disposed on the -Y direction side and the second idler 53b disposed on the +Y direction side. In addition, both or one of the idlers 53 abut against the edge of the lower end of the bottom surface portion 63 of the first dog 60a. In this position, as described above, the clamp unit 40 including the clamper 430 is held at the uppermost position, and the clamp of the sheet 510 is released.

[0063] In this state, if the operator does not intend to move the cutter unit 50, i.e., does not grip the cutter arm 54 to move it horizontally, the above-mentioned characteristic shape of the first dog 60a prevents the cutter unit 50 from moving in the +Y direction on its own. First, the edge of the lower end of the bottom surface portion 63 is shaped to have a slight upward inclination of angle θ2 with respect to the horizontal as it approaches the -Y direction. Therefore, even if the cutter unit 50 naturally tries to move in the +Y direction, a reaction force that pushes the idler 53 down in the -Z direction from the bottom surface portion 63 of the first dog 60a and a reaction force that returns the idler 53 to the -Y direction are applied, so that the cutter unit 50 is prevented from easily moving in the +Y direction.

[0064] Furthermore, a protrusion 64 is provided that protrudes locally below the first dog 60a at the boundary between the inclined portion 62 and the bottom surface portion 63 of the edge of the lower end of the first dog 60a. Therefore, when the cutter unit 50 naturally tries to move in the +Y direction, it becomes difficult for the cutter unit 50 to start moving in the +Y direction unless a force is applied that returns the idler 53 to the -Y direction and overcomes the stronger reaction force received from the protrusion 64.

[0065] Next, when the operator grasps the cutter arm 54 and tries to move it in the +Y direction with a certain degree of strong force, the second idler 53b and the first idler 53a sequentially push up the protrusion 64 of the first dog 60a, as shown in FIG. 6(c). Thereafter, as shown in FIG. 7(a), the cutter unit 50 moves to position L2 in FIG. 2(c). At this time, the first idler 53a of the idler 53 abuts against the inclined portion 62 of the first dog 60a. The distance between the idler 53 and the first dog 60a in the vertical direction is closer than at position L1, so the vertical position of the first dog 60a is relatively lower than at position L1.

[0066] Therefore, at this time, the vertical position of the clamper 430, which is linked to the position of the first dog 60a, is also lower than that at position L1, so that the distance between the clamper 430 and the guide rail 330 is shortened.

[0067] If the operator further moves the cutter arm 54 in the +Y direction while holding it, both the first idler 53a and the second idler 53b are in a positional relationship separated from the first dog 60a, as shown in FIG. 7(b). That is, the idler 53 directly contacts the upper linear shaft 410 without the first dog 60a. At this time, the cutter unit 50 moves to position L3 in FIG. 3(a). At this time, the idler 53 and the first dog 60a along the vertical direction are closest to each other, and the vertical position of the first dog 60a is at its lowest relative position.

[0068] At this time, the clamper 430 is also at its lowest position in the vertical direction, and the clamper 430 presses the sheet 510 against the guide rails 330 , that is, the clamper 430 clamps the sheet 510 to the guide rails 330 .

[0069] Thereafter, the operator grasps the cutter arm 54 and moves it in the +Y direction from position L3 to position L4 shown in FIG. 3(b), thereby allowing the sheet 510 clamped by the clamper 430 to be accurately cut widthwise. When the position of the cutter arm 54 along the Y axis is within a predetermined range from L3 to L4, the clamper 430 can properly clamp both ends of the sheet 510 placed on the guide rail 330. When the position of the cutter arm 54 along the Y axis is within the predetermined range, the idler 53 does not come into contact with the dog 60, and the clamper 430 linked to the dog 60 is lowered to the lowest position, and the clamper 430 is pressed against the guide rail 330.

[0070] The first dog 60a and the second dog 60b are arranged symmetrically with respect to one end and the other end of the sheet 510 in the direction along the Y axis. That is, the first dog 60a is arranged at a position further on the -Y direction side and above the end of the sheet 510 placed on the guide rail 330. The second dog 60b is arranged at a position further on the +Y direction side and above the end of the sheet 510 placed on the guide rail 330 in the +Y direction.

[0071] Therefore, when the operator grasps the cutter arm 54 and tries to move it further from position L4 in the +Y direction, the state is the same as when the shape of the first dog 60a is reversed symmetrically in FIG. 7(a), although this is not shown. That is, the cutter unit 50 moves to position L5 in FIG. 4(a). At this time, the second idler 53b of the idler 53 abuts against the inclined portion 62 of the second dog 60b. At this time, the distance between the idler 53 and the second dog 60b in the vertical direction is farther apart than at position L4 and closer than at position L1, so that the vertical position of the second dog 60b is relatively higher than at position L4 and lower than at position L1.

[0072] Next, when the operator grasps the cutter arm 54 and tries to move it in the +Y direction with a certain degree of strong force, the state becomes the same as when the shape of the first dog 60a is reversed symmetrically in FIG. 6(b), although this is not shown in the figure. That is, the first idler 53a and the second idler 53b each push up the protrusion 64 of the second dog 60b in turn. Then, both or one of the idlers 53 move to position L6 in FIG. 4(b) where they abut against the lower edge of the bottom surface portion 63 of the second dog 60b. At this position, as in position L1, the clamp unit 40 including the clamper 430 is held at the uppermost position, and the clamp of the sheet 510 is released.

[0073] [b] Sheet cutting method using a sheet cutting device Next, a method for cutting the sheet 510 wound around the roll 500 in the width direction to a predetermined length using the above-mentioned sheet cutting device 1 will be described mainly based on the front view of the sheet cutting device 1 in FIG. 8 as seen from the -Y direction side and the flow diagram in FIG. 9.

[0074] First, a roll 500 on which a packaging sheet 510 such as an air cap is wound in a roll shape is set in the supply unit 10 (step S601 in FIG. 9). As a result, the roll 500 is rotatably supported so that the sheet 510 can be manually unwound from the roll 500 on which the sheet 510 is wound.

[0075] Next, the sheet 510 is fed to a predetermined position in the sheet cutting device 1 while taking into consideration the cutting length (step S602). Specifically, as shown in Fig. 8(a), the sheet 510 indicated by the thick line is once lifted from the roll 500 to a position of the first guide frame 13 slightly diagonally above the roll 500 and hung thereon, and then hung on the second guide frame 14 at the lower end. At this time, the position of the cutter arm 54 in the first direction along the Y axis is set to the outside (position L1) of a predetermined range that is a range sandwiched between positions L3 and L4, and the cutting position of the sheet 510 is specified in a state where the clamp of the sheet 510 is released.

[0076] Here, the amount of sheet 510 to be pulled out can be determined by referring to, for example, the tape measure 220 shown in FIG. 1. Alternatively, the sheet 510 may be provided with markings indicating the cutting position in advance. This allows the sheet 510 to be accurately unwound by the required predetermined length. When the sheet 510 is pulled out to the vicinity of the cutting section 30 and the clamping section 40, as shown in FIG. 8(b), the sheet 510 that has passed under the second guide frame 14 is passed over the base plate 210 that is disposed at a certain distance from the second guide frame 14 along the X-axis direction. Here, when the distance between the second guide frame 14 and the base plate 210 along the X-axis direction is d2, this distance can be adjusted by moving either the second guide frame 14 or the base plate 210 along the X-axis direction.

[0077] By adjusting the above-mentioned separation distance, it is possible to provide an appropriate tension to the sheet 510. In general, when the diameter of the roll 500 is large, a relatively large force is required to pull out the sheet 510 due to the influence of the moment of inertia of the roll 500, and when the diameter is large or small, less force is required to pull out the sheet 510. In this way, if the tension applied to the sheet 510 varies due to the variation in the diameter of the roll 500, it may become difficult to stably and accurately cut the sheet 510, so it is also effective to provide a tension adjustment mechanism as described above.

[0078] Next, the cutter arm 54 is slid in a predetermined direction (horizontal direction) (step S603). As a result, the sheet 510 is automatically clamped in accordance with the sliding of the cutter arm 54, and then cutting begins (step S604). In other words, the position of the cutter arm 54 along the Y axis is sequentially moved from outside the predetermined range between positions L3 and L4 to within the predetermined range, whereby the sheet 510 is cut along the direction along the Y axis while being clamped by the clamper 430.

[0079] Thereafter, the cutter arm 54 slides to the end, automatically releasing the clamp on the sheet 510 (step S605). That is, the cutter arm 54 is moved until cutting of the sheet 510 is completed and the position of the cutter arm 54 along the Y-axis direction is outside the predetermined range (position L6), and the clamp on the sheet 510 is released.

[0080] Thereafter, if cutting of the sheet 510 is to be continued, the process returns to step S602 and the subsequent steps are repeated. That is, the sheet 510 is fed to a predetermined position in the sheet cutting device 1 while taking into consideration the cutting length. Then, the cutter arm 54 is slid in a predetermined direction (horizontally). However, if the cutter arm 54 was previously slid from the -Y direction side toward the +Y direction side to cut the sheet 510, the next cut will be performed by sliding the cutter arm 54 from the +Y direction side toward the -Y direction side to cut the sheet 510.

[0081] That is, when cutting the sheet 510 continues after the previous cutting of the sheet 510, the cutter arm 54 is slid in the opposite direction to the previous cutting. The cutter blade 55 of the sheet cutting device 1 has a double-edged blade tip 55a, with a first blade 55p facing the -Y direction and a second blade 55q facing the +Y direction. Therefore, the efficiency of the cutting operation of the sheet 510 is significantly improved compared to a cutter blade that is only attached to one side and cannot be cut unless it is slid from the -Y direction to the +Y direction, for example. [Explanation of symbols]

[0082] 1 Sheet cutting device 10 Supply section 11 Shaft support frame 11a First shaft support frame 11b Second shaft support frame 12 Roll shaft 13 First guide frame 14 Second guide frame 15 Base frame 15a First base frame 15b Second base frame 30 Cut section 40 Clamp section 50 Cutter unit 51 Slider 52 Mounting block 53 Idler 53a 1st idler 53b 2nd Idler 54 Cutter Arm 55 Cutter blade 55a cutting edge 55p 1st blade 55q 2nd blade 60 Dog 60a 1st Dog 60b 2nd Dog 61 Fixed part 62 Slope 63 Bottom part 64 Protrusion 210 Base Plate 220 Major 310 Linear Shaft 320 Support shaft 320a first support shaft 320b second support shaft 320c protrusion 330 Guide Rail 330a Slit 410 Linear Shaft 420 Support shaft 420a first support shaft 420b second support shaft 430 Clamper 430a 1st Clamper 430b 2nd Clamper 440 Lifting section 440a First lift section 440b Second lift section 500 rolls 510 seats

Claims

1. a supply unit that rotatably supports a roll around which the sheet is wound so that the sheet can be unwound from the roll; A cutting unit that cuts the sheet; a clamp portion that clamps the sheet, The cutting portion is A guide rail having a groove formed along a first direction; a linear shaft spaced a predetermined distance from the guide rail and extending along the first direction; a cutter arm fixed to the linear shaft so as to be movable along the first direction and having a cutter blade at a tip thereof; the cutter arm includes a first clamp adjustment member and is movable along the first direction with the cutter blade inserted in the groove; The clamp portion is a clamp piece capable of clamping the sheet placed on the guide rail; A second clamp adjustment member; a lifting section that fixes the clamp piece and the second clamp adjustment member so that they can be raised and lowered, When the position of the cutter arm along the first direction is within a predetermined range, the first clamp adjustment member does not push up the second clamp adjustment member, and the sheet is clamped, A sheet cutting device in which, when the position of the cutter arm along the first direction is outside the specified range, the first clamp adjustment member pushes up the second clamp adjustment member, and the clamp piece and the second clamp adjustment member are raised by the lifting section, thereby releasing the clamp on the sheet.

2. The sheet cutting device according to claim 1 , wherein the predetermined range includes at least a range in a width direction in which the sheet exists.

3. 2. The sheet cutting device of claim 1, wherein the cutter arm has blades on both sides along the first direction so that the sheet can be cut in either one or the other direction along the first direction when the cutter blade is inserted into the groove.

4. The sheet cutting device according to claim 1 , wherein the second clamp adjustment members are arranged in bilateral symmetry at positions corresponding to one end side and the other end side of the sheet along the first direction.

5. The second clamp adjustment member has a sloped portion at a lower end edge having a predetermined slope angle and a bottom surface portion that is substantially horizontal, The sheet cutting device according to claim 1 , wherein the position of the lower edge portion gradually decreases along the inclined portion as it moves outward in the first direction, and the position is lowest at the bottom surface portion.

6. The sheet cutting device according to claim 5 , wherein the edge of the lower end of the bottom surface portion has an upward inclination of 5° or more and 10° or less with respect to the horizontal as it extends outward along the first direction.

7. 7. The sheet cutting device according to claim 5, wherein the second clamp adjustment member has a shape having a protrusion that locally protrudes downward at a boundary between the inclined portion and the bottom surface portion of the edge of the lower end.

8. rotatably supporting a roll on which the sheet is wound so that the sheet can be unwound from the roll; unwinding a predetermined length of the sheet from the roll; a step of determining a cutting position of the sheet while the position of the cutter arm along the first direction is outside a predetermined range and the clamp of the sheet is released; a step of cutting the sheet along the first direction while clamping the sheet by sequentially moving a position of the cutter arm along the first direction from outside the predetermined range to within the predetermined range; a step of moving the cutter arm until cutting is completed and the position of the cutter arm along the first direction is outside the specified range, thereby releasing the clamp on the sheet.

Images