Embossing machine compatible with pre-printed embossed materials

Abstract

The present invention provides an embossing apparatus that embosses printed text, graphics, and other images while maintaining their readability, even when printed on embossed material, without compromising the legibility of the text or graphics due to the unevenness created on the embossed material. [Solution] In an embossing apparatus in which a first roller 110U and a second roller 110D are arranged opposite each other to perform embossing using the uneven surfaces of the first and second rollers, the distance between the protrusions of the first and second rollers is set to be a certain distance greater than the width of the protrusions. This prevents the slopes from becoming steep, from the protrusions to the recesses and from the recesses to the protrusions of the embossed material, and makes the slopes gentler, thereby maintaining the visibility of printed characters, figures, and other images in the sloped areas. The embossing apparatus is configured to emboss the embossed material into a truncated square pyramidal shape.

Description

Technical Field

[0004] , ,

[0001] The present utility model relates to an embossing device for embossing an embossed material, and even when printed on the embossed material, it relates to an embossing device that performs embossing while maintaining the legibility of images such as printed characters and graphics.

Background Art

[0002] Conventionally, a second embossing roller having opposite concavities and convexities is arranged opposite to a first embossing roller having concavities and convexities for embossing an embossed material such as kraft paper. By passing the embossed material inserted from the insertion port between the first and second embossing rollers, pressing is performed to generate an embossed material with a large number of bubble-shaped concavities and convexities. An embossing device is known.

[0003] [[ID=十五]] Patent Document 1 (Utility Model Registration No. 3247328) discloses a first embossing roll having a large number of bubble-shaped convex portions on its circumferential surface for forming a large number of bubble-shaped concave portions on a web-shaped paper, and a second embossing roll provided opposite to the first embossing roll and having a large number of bubble-shaped convex portions on its circumferential surface for forming a large number of bubble-shaped concave portions on the web-shaped paper inserted from the insertion port. By passing the web-shaped paper between the opposing first embossing roll and second embossing roll, pressing is performed to discharge a bubble-shaped processed buffer paper in which a large number of bubble-shaped concave portions are formed over the entire surface of the web-shaped paper. The invention is described.

Prior Art Documents

Patent Documents

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When embossing is applied to embossed materials such as kraft paper that have images such as letters and shapes printed on them, the embossed material becomes uneven, and this unevenness can impair the visibility of the letters, shapes, and other images. [Means for solving the problem]

[0005] The system comprises a first roller that is rotationally driven, and a second roller that is positioned opposite the first roller so that the material to be embossed can be inserted between the first roller and the second roller that is rotationally driven together with the first roller to emboss the material to be embossed. The first roller and the second roller have intermittently protruding rectangular prism-shaped or truncated square pyramidal protrusions along the circumferential direction of their outer surfaces for embossing, and adjacent protrusions are spaced apart by a certain distance. Multiple first rollers are arranged along the axis of rotation, Multiple second rollers are arranged along the axis of rotation, The convex portion of one first roller and the concave portion of the other first roller, which are adjacent to each other along the axis of rotation, are arranged to be adjacent to each other along the axis of rotation, The convex portion of one second roller and the concave portion of the other second roller, which are adjacent to each other along the axis of rotation, are arranged to be adjacent to each other along the axis of rotation. The protrusions of two adjacent first rollers along the axis of rotation and the protrusions of two adjacent second rollers along the axis of rotation are arranged at a second fixed distance apart so as to emboss the material to be embossed into a truncated square trapezoid shape so that images such as characters and figures printed on the material to be embossed can be recognized. This constitutes an embossing machine. [Effects of the Invention]

[0006] By arranging adjacent protrusions of the first roller and adjacent protrusions of the second roller at a distance greater than a first certain distance, and by arranging adjacent protrusions of the first rollers along the axis of rotation and adjacent protrusions of the second rollers along the axis of rotation at a distance greater than a second certain distance, the steep inclines of the embossed material, from protrusions to recesses and from recesses to protrusions, are prevented.

[0007] If the slope from a convex to a concave area becomes too steep, the letters and figures printed on the embossed material will be extremely tilted, making them difficult to read. Therefore, by spacing the convex areas of the first and second embossing rollers apart by a certain distance or more, the slopes from the convex to the concave area and from the concave to the convex area will not become too steep, resulting in gentler slopes. This reduces distortion of the letters and figures printed on the embossed material, thus maintaining their readability. Furthermore, by reducing distortion of the embossed material, tearing of the embossed material can also be prevented, further maintaining the readability of the printed letters and figures. [Brief explanation of the drawing]

[0008] [Figure 1A] Figure 1A is a top view of the embossing apparatus of the embodiment, viewed from above. [Figure 1B] Figure 1B is a front view of the embossing apparatus of the embodiment, viewed from the front. [Figure 2A] Figure 2A is a perspective view of the embossing machine from the left side, as seen from the arrow A in Figure 1A. [Figure 2B] Figure 2B is a perspective view of the embossing machine from the right side, as seen from the arrow B in Figure 1A. [Figure 3A] Figure 3A shows the internal structure of the drive unit in Figure 2A. [Figure 3B] Figure 3B is a perspective view of the CC cross section shown in Figure 1A. [Figure 4A]Figures 4A(A) and (B) are respectively a front view and a side view of one of the pair of roller members constituting the first roller and the second roller. [Figure 4B] Figures 4B(A) and (B) are respectively a front view and a side view of the other of the pair of roller members constituting the first roller and the second roller. [Figure 5] Figure 5 is a perspective view showing a state where a plurality of roller members are inserted along the axial direction of the first shaft. [Figure 6] Figure 6 is a view of the state where the first roller and the second roller are arranged facing each other as seen from the side. [Figure 7] Figure 7 is a view of the state where the first roller and the second roller are arranged facing each other with the outer peripheral surface facing forward. [Figure 8] Figure 8 is a view showing an embossed material discharged from between the first roller and the second roller. [Figure 9] Figure 9 is a plan view showing an embossed material after embossing. [Figure 10] Figure 10 is a figure corresponding to Figure 6 and is a figure for explaining the shape of an emboss formed by the first roller and the second roller. [Figure 11] Figures 11(A) and (B) are figures for explaining the shear stress generated in the embossed material according to the distance in the rotational axis direction between the convex portions. [Figure 12] Figure 12 is a view of the first roller and the second roller showing the dimensions of each part as seen from the side. [Figure 13] Figure 13 is a figure showing an example of a character image printed on an embossed material. [Figure 14] Figure 14 is a figure showing the result of calculating the distortion of an image when an embossed material printed with a character image is embossed under the first condition. [Figure 15] Figure 15 is another figure showing the result of calculating the distortion of an image when an embossed material printed with a character image is embossed under the second condition.

Embodiment for Carrying Out the Invention

[0009] The first form includes a first roller that is rotationally driven, and a second roller that is disposed to face the first roller such that a material to be embossed can be inserted between the first roller and the second roller, and the second roller is rotationally driven together with the first roller so as to emboss the material to be embossed. On the first roller and the second roller, convex portions having a square prism shape or a truncated square pyramid shape for performing embossing are intermittently provided along the circumferential direction of the outer peripheral surface. Adjacent convex portions of the first roller and the second roller are arranged at a certain distance apart so that an image such as characters and figures printed on the material to be embossed can be recognized, and in a side view of the first roller and the second roller, the material to be embossed is embossed into a trapezoid, which is an embossing device configured as such.

[0010] The second form is, in the first form, a plurality of first rollers are arranged along the rotational axis direction, and a plurality of second rollers are arranged along the rotational axis direction. The convex portion of one first roller and the concave portion of the other first roller adjacent along the rotational axis direction are arranged to be adjacent along the rotational axis direction, and the convex portion of one second roller and the concave portion of the other second roller adjacent along the rotational axis direction are arranged to be adjacent along the rotational axis direction. The convex portions of both first rollers adjacent along the rotational axis direction and the convex portions of both second rollers adjacent along the rotational axis direction are arranged at a certain distance apart so that an image such as characters and figures printed on the material to be embossed can be recognized, and the material to be embossed is embossed into a truncated square pyramid shape, which is an embossing device configured as such.

[0011] The third form is, in the first or second form, an embossing device in which the circumferential surface between both adjacent convex portions along the circumferential direction of the outer peripheral surface of the first roller and the second roller is formed to be flat or substantially flat.

[0012] The fourth embodiment is an embossing apparatus in which, in the first or second embodiment, the width of the outer circumferential surface of the first roller and the second roller is formed to be wider than the width of the protrusion.

[0013] The fifth embodiment is an embossing apparatus in which, in the first or second embodiment, four or five of the protrusions are provided at equal intervals along the circumferential direction of the outer surfaces of the first roller and the second roller.

[0014] The sixth embodiment is an embossing apparatus in which, in the first or second embodiment, the corners of the protrusions projecting along the circumferential direction of the outer surfaces of the first roller and the second roller are chamfered with R-chamfers or C-chamfers.

[0015] The seventh embodiment is an embossing apparatus in which, in the first or second embodiment, the edges of the protrusions projecting along the circumferential direction of the outer surfaces of the first roller and the second roller are chamfered with R-chamfers or C-chamfers.

[0016] The eighth embodiment is an embossing apparatus in which, in the second embodiment, the first roller has a first shaft insertion hole formed therein, and the second roller has a second shaft insertion hole formed therein, and comprises a first shaft through which a plurality of first rollers are inserted axially along the first shaft insertion hole, and a second shaft through which a plurality of second rollers are inserted axially along the second shaft insertion hole, wherein the convex portion of one first roller and the concave portion of the other first roller adjacent to each other along the axial direction of the first shaft are arranged to be adjacent along the axial direction, and the convex portion of one second roller and the concave portion of the other second roller adjacent to each other along the axial direction of the second shaft are arranged to be adjacent along the axial direction.

[0017] The ninth embodiment is an embossing apparatus in which, in the eighth embodiment, the first shaft has a first key groove formed along the axial direction, a first key protruding from the inner circumferential surface of the first roller that fits into the first key groove, the second shaft has a second key groove formed along the axial direction, a second key protruding from the inner circumferential surface of the second roller that fits into the second key groove, the first keys of one adjacent first roller and the first key of the other first roller protrude at positions offset along the circumferential direction of the inner circumferential surface of the first shaft, and the second keys of one adjacent second roller and the other second roller protrude at positions offset along the circumferential direction of the inner circumferential surface of the second shaft.

[0018] The tenth embodiment is an embossing apparatus in which, in the eighth embodiment, a first key is provided projecting from the first shaft along the axial direction, a first key groove is formed on the inner circumferential surface of the first roller into which the first key is fitted, a second key is provided projecting from the second shaft along the axial direction, a second key groove is formed on the inner circumferential surface of the second roller into which the second key is fitted, the first key grooves of one adjacent first roller and the first key groove of the other adjacent first roller along the axial direction of the first shaft are formed at offset positions along the circumferential direction of the inner circumferential surface, and the second key grooves of one adjacent second roller and the second key groove of the other adjacent second roller along the axial direction of the second shaft are formed at offset positions along the circumferential direction of the inner circumferential surface.

[0019] The eleventh embodiment is an embossing apparatus comprising, in the second embodiment, a first support member that rotatably supports the end of the first shaft, a first holding portion that holds the first support member, a second support member that rotatably supports the end of the second shaft, a second holding portion that holds the second support member and is positioned opposite the first holding portion, and a biasing member that biases at least one of the first and second holding portions in a direction that causes one holding portion to come into contact with the other holding portion, and also applies a biasing force such that the one holding portion moves in a direction that causes it to move away from the other holding portion as the material to be embossed is inserted.

[0020] The twelfth embodiment is an embossed material manufactured by inserting a material to be embossed between a first roller and a second roller, each roller having intermittently protruding rectangular prism-shaped or truncated square pyramidal protrusions along the circumferential direction of its outer surface, wherein the material has raised embossing on the front surface and raised embossing on the back surface in a checkerboard pattern when viewed from above, the raised embossing is formed in a truncated square pyramidal shape, and adjacent raised embossings are connected by wrinkles. [Examples] Hereinafter, an embodiment of the embossing apparatus according to the present invention will be described with reference to the drawings.

[0021] (Overall configuration of the embossing machine 200)

[0022] Figure 1A shows a top view of the embossing apparatus 200 of the embodiment, viewed from above. The material to be embossed is supplied from the bottom of Figure 1A, and the embossed material is discharged from the top of Figure 1A. The direction of transport of the material to be embossed is indicated by an arrow. The left side of Figure 1A is defined as the left side of the embossing apparatus 100, and the right side of Figure 1A is defined as the right side of the embossing apparatus 100.

[0023] Figure 1B shows a front view of the embossing apparatus 100 of the embodiment. The material to be embossed is supplied from the front side in Figure 1B, and the embossed material is discharged from the back side in Figure 1B. The left side in Figure 1B is defined as the left side of the embossing apparatus 100, and the right side in Figure 1B is defined as the right side of the embossing apparatus 100.

[0024] The material to be embossed is, for example, kraft paper. The embossed material is used, for example, as cushioning material.

[0025] The embossing apparatus 100 is broadly composed of a support base 210, a frame section 220, a drive section 230, a driven section 240, a shaft left end support section 250L, a shaft right end support section 250R, a first roller section 100U, and a second roller section 100D. In this embodiment, the first roller section 100U constitutes the driven roller section, and the second roller section 100D constitutes the drive roller section.

[0026] Vibration-damping rubber 211 is attached to the corners of the lower surface of the support base 210, and the support base 210 is placed on the ground via the vibration-damping rubber 211. Vibration-damping rubber 212 is attached to the left and right sides of the upper surface of the support base 210, and the left and right plate members 221L and 221R of the frame section 220 are supported via the vibration-damping rubber 212.

[0027] The frame section 220 is fitted with the drive section 230, the driven section 240, the left end support section 250L of the shaft, and the right end support section 250R of the shaft.

[0028] The first roller section 100U is located on the upper side of the frame section 220 and consists of a first shaft 120U and a plurality of first rollers 110U that are fixed to the first shaft 120U.

[0029] The second roller section 100D is located below the frame section 220 and is positioned opposite the first roller section 100U. It consists of a second shaft 120D and a plurality of second rollers 110D that are fixed to the second shaft 120D.

[0030] The left end support portion 250L and the right end support portion 250R of the shaft support portions 100U and 100D respectively support the left and right ends of the first roller portion 100U and the second roller portion 100D so that they can rotate freely. The drive portion 230 and the driven portion 240 rotate the first roller portion 100U and the second roller portion 100D.

[0031] Figure 2A is a perspective view of the embossing machine 200 from the left side, as seen from arrow A in Figure 1A. Figure 2A is a view of the drive unit 230 from the outside of the frame unit 220.

[0032] Figure 2B is a view B of the arrow in Figure 1A, and is a perspective view of the embossing machine 200 from the right side. Figure 2B is a view of the driven part 240 from the outside of the frame part 220.

[0033] Figure 3A shows the internal structure of the drive unit 230 in Figure 2A.

[0034] Figure 3B shows a perspective view of the CC cross section of Figure 1A. Figure 3B is a view of the driven part 240 from the inside of the frame part 220.

[0035] (Configuration of frame section 220)

[0036] The frame section 220 is composed of a left plate member 221L, a right plate member 221R, discharge-side guide plate members 222 (222U, 222D), supply-side guide plate members 223 (223U, 223D), and connecting members 224 (224UA, 224UB, 224DA, 224DB).

[0037] The left plate member 221L has the drive unit 230 and the left end support unit 250L of the shaft attached to it. The right plate member 221R has the driven unit 240 and the right end support unit 250R of the shaft attached to it.

[0038] The supply-side guide plate members 223 (223U, 223D) are plate-shaped members that are located inside the frame portion 220 and on the supply side, extending in the left-right direction. The supply-side guide plate members 223 (223U, 223D) connect the left plate member 221L and the right plate member 221R. The supply-side guide plate member 223 consists of an upper supply-side guide plate member 223U and a lower supply-side guide plate member 223D. By inserting the material to be embossed between the upper supply-side guide plate member 223U and the lower supply-side guide plate member 223D, the material to be embossed can be guided and moved between the first roller portion 100U and the second roller portion 100D. The material to be embossed is inserted into the embossing device 100 from a tray. Here, a guide that supports and guides the lower surface of the material to be embossed, and a roller member that rolls on the upper surface of the material to be embossed, may be provided between the tray and the supply-side guide plate member 223, so as to smoothly feed the material to be embossed from the tray to the embossing device 100.

[0039] The discharge-side guide plate members 222 (222U, 222D) are plate-shaped members that are located inside the frame portion 220 and on the discharge side, extending in the left-right direction. The discharge-side guide plate members 222 (222U, 222D) connect the left plate member 221L and the right plate member 221R. The discharge-side guide plate member 222 consists of an upper discharge-side guide plate member 222U and a lower discharge-side guide plate member 222D. The embossed material discharged from between the first roller portion 100U and the second roller portion 100D is guided and moved between the upper discharge-side guide plate member 222U and the lower discharge-side guide plate member 222D, allowing the embossed material to be removed.

[0040] The connecting members 224 (224UA, 224UB, 224DA, 224DB) are pipe-shaped members located inside the frame portion 220 and extending in the left-right direction. The connecting members 224UA, 224UB, 224DA, and 224DB connect the left plate member 221L and the right plate member 221R at the discharge side and upper position, the supply side and upper position, the discharge side and lower position, and the supply side and lower position, respectively.

[0041] (Configuration of drive unit 230 and driven unit 240)

[0042] The drive unit 230 consists of a motor 231, a first gear 232, and a second gear 233. The first gear 232 is fixed to the rotating shaft 231A of the motor 231. The first gear 232 meshes with the second gear 233. The second gear 233 is fixed to the left end of the second shaft 120D of the second roller unit 100D. As a result, the rotational driving force of the motor 231 is transmitted to the second shaft 120D of the second roller unit 100D via the rotating shaft 231A, the first gear 232, and the second gear 233, thereby rotating the second roller unit 100D.

[0043] The driven section 240 includes a third gear 241 and a fourth gear 242. The third gear 241 is fixed to the right end of the second shaft 120D of the second roller section 100D. The third gear 241 meshes with the fourth gear 242. The fourth gear 242 is fixed to the right end of the first shaft 120U of the first roller section 100U. As a result, the rotational driving force of the motor 231 is transmitted to the first shaft 120U of the first roller section 100U via the rotating shaft 231A, the first gear 232, the second gear 233, the second shaft 120D of the second roller section 100D, the third gear 241, and the fourth gear 242, thereby rotating the first roller section 100U.

[0044] (Configuration of shaft left end support part 250L and shaft right end support part 250R)

[0045] The left end support portion 250L of the shaft is composed of a first shaft roller bearing 251L, a second shaft roller bearing 252L, a bearing outer ring support portion 253L, a sliding plate 254L, a coil spring 255L, and a coil spring support portion 256L.

[0046] The first shaft roller bearing 251L rotatably supports the left end of the first shaft 120U. The second shaft roller bearing 252L rotatably supports the left end of the second shaft 120D.

[0047] The bearing outer ring support portion 253L is fixed to the left plate member 221L. The bearing outer ring support portion 253L holds the outer circumference of the second shaft roller bearing 252L in a fixed position, and also holds the lower outer circumference of the first shaft roller bearing 251L in a movable position.

[0048] The sliding plate 254L is supported by the left plate member 221L so as to be slidable in the vertical direction. The sliding plate 254L holds the upper outer circumference of the first shaft roller bearing 251L in a fixed position.

[0049] A coil spring fitting portion 254A is provided protruding from the sliding plate 254L. The lower side of the coil spring 255L is fitted into the coil spring fitting portion 254A.

[0050] The coil spring support portion 256L is fixed above the left plate member 221L. The upper end of the coil spring 255L is in contact with the coil spring support portion 256L.

[0051] Similarly, the shaft right end support portion 250R is composed of a first shaft roller bearing 251R, a second shaft roller bearing 252R, a bearing outer ring support portion 253R, a sliding plate 254R, a coil spring 255R, and a coil spring support portion 256R.

[0052] Similarly, the first shaft roller bearing 251R rotatably supports the right end of the first shaft 120U. The second shaft roller bearing 252R rotatably supports the right end of the second shaft 120D.

[0053] The bearing outer ring support portion 253R is fixed to the right plate member 221R. The bearing outer ring support portion 253R holds the outer circumference of the second shaft roller bearing 252R in a fixed position, and also holds the lower outer circumference of the first shaft roller bearing 251R in a movable position.

[0054] The sliding plate 254R is supported by the right plate member 221R so as to be slidable in the vertical direction. The sliding plate 254R fixes and holds the upper outer circumference of the first shaft roller bearing 251R.

[0055] A coil spring fitting portion 254A is provided protruding from the sliding plate 254R. The lower side of the coil spring 255R is fitted into the coil spring fitting portion 254A.

[0056] The coil spring support portion 256R is fixed above the right plate member 221R. The upper end of the coil spring 255R is in contact with the coil spring support portion 256R.

[0057] Here, the spring force of the coil spring 255L causes the sliding plate 254L to contact the bearing outer ring support portion 253L when the material to be embossed is not inserted between the first roller portion 100U and the second roller portion 100D, thereby suppressing the movement of the first roller portion 100U. However, when the material to be embossed is inserted between the first roller portion 100U and the second roller portion 100D, the sliding plate 254L moves away from the bearing outer ring support portion 253L in accordance with the thickness of the material to be embossed, against the spring force, causing the first roller portion 100U to move upward. It is desirable to adjust the spring force of the coil spring 255L to such an extent that this effect occurs. The same applies to the spring force of the coil spring 255R.

[0058] Note that coil springs 255L and 255R are just examples, and it is also possible to use any elastic member that provides an elastic force similar to that of a spring, or any biasing member that provides a biasing force similar to that of a spring.

[0059] As described above, in this embodiment, the end of the first shaft 120U is rotatably supported by the first shaft roller bearings 251L and 251R, the first shaft roller bearings 251L and 251R are held by the sliding plates 254L and 254R, the end of the second shaft 120D is rotatably supported by the second shaft roller bearings 252L and 252R, and the bearing outer ring support portions 253L and 252R are arranged opposite the sliding plates 254L and 254R. 53R holds the second shaft roller bearings 252L, 252R, and coil springs 255L, 255R provided on the sliding plates 254L, 254R bias the sliding plates 254L, 254R in a direction that brings them into contact with the bearing outer ring support portions 253L, 253R, and also apply a biasing force such that the sliding plates 254L, 254R move away from the bearing outer ring support portions 253L, 253R as the embossed material is inserted.

[0060] However, this is just one example, and the bearing outer ring support portions 253L and 253R may be equipped with biasing members similar to coil springs 255L and 255R, thereby making the bearing outer ring support portions 253L and 253R movable.

[0061] In other words, the device comprises a first support member that rotatably supports the end of a first shaft 120U, a first holding portion that holds the first support member, a second support member that rotatably supports the end of a second shaft 120D, and a second holding portion that holds the second support member and is positioned opposite the first holding portion. The device is configured such that at least one of the first and second holding portions is provided with a biasing member, which biases one holding portion to come into contact with the other holding portion and also applies a biasing force such that one holding portion moves away from the other holding portion as the material to be embossed is inserted.

[0062] By adopting this configuration, it is possible to suppress tearing of the material to be embossed during the embossing process.

[0063] (Configuration of the first roller section 100U and the second roller section 100D)

[0064] Figures 4A(A) and (B) are a front view and a side view, respectively, of one of the pair of roller members 111 that make up the first roller 110U and the second roller 110D.

[0065] Figures 4B(A) and (B) are a front view and a side view, respectively, of the other roller member 112 of the pair of roller members that make up the first roller 110U and the second roller 110D.

[0066] In Figures 1A and 1B, one roller member 111 is shown in white and the other roller member 112 is shown in hatched to distinguish them.

[0067] (Shape of the pair of roller members 111 and 112 that constitute the first roller 110U and the second roller 110D)

[0068] As shown in Figures 4A(A), (B) and 4B(A), (B), the outer circumferential surfaces 113 of the roller members 111 and 112 are intermittently provided with rectangular prism-shaped protrusions 114 along the circumferential direction for embossing. In this specification, the rectangular prism-shaped protrusions 114 are not limited to perfectly rectangular prism-shaped protrusions 114, but include substantially rectangular prism-shaped protrusions 114 depending on the draft angle and other factors that are permissible in design and manufacturing. Furthermore, the protrusions 114 may be formed in the shape of a truncated square pyramid, insofar as the effects of the embodiment are achieved.

[0069] Five protrusions 114 are provided at equal intervals along the circumferential direction of the outer surface 113 of the roller members 111 and 112. Alternatively, four protrusions 114 may be provided at equal intervals along the circumferential direction of the outer surface 113 of the roller members 111 and 112.

[0070] A recess 115 is formed between adjacent protrusions 114 along the circumferential direction of the outer peripheral surface 113 of the roller members 111 and 112.

[0071] The circumferential surface 113A between adjacent protrusions 114 along the circumferential direction of the outer circumferential surface 113 of the roller members 111 and 112 is formed flat. In this specification, "flat" of the circumferential surface 113A is not limited to "perfectly flat," but also includes cases where it is substantially flat.

[0072] The width 113W of the outer circumferential surface 113 of the roller members 111 and 112 is wider than the width 114W of the protrusion 114. The width difference d between the width 113W of the outer circumferential surface and the width 114W of the protrusion 114 is adjusted to a value necessary to make the emboss 301 into a desired truncated square pyramidal shape, as will be described later.

[0073] The corners 114N of the protrusions 114 that are provided along the circumferential direction of the outer surface 113 of the roller members 111 and 112 are rounded off.

[0074] The corners 114N of the protrusion 114 are machined into a circular shape with a radius of, for example, 0.5 mm. Alternatively, the corners 114N of the protrusion 114 may be chamfered.

[0075] Furthermore, the edges 114E of the protrusions 114 that protrude along the circumferential direction of the outer circumferential surface 113 of the roller members 111 and 112 are chamfered with a rounded edge (R). Alternatively, the edges 114E of the protrusions 114 may be chamfered with a rounded edge (C).

[0076] The roller members 111 and 112 have shaft insertion holes 118 formed therein. The outer circumference of the shaft insertion hole 118 constitutes the inner circumferential surface 116 of the roller members 111 and 112.

[0077] A key 117 is provided protruding from the inner circumferential surface 116 of one of the roller members 111. The key 117 of the one roller member 111 is positioned so that its central axis coincides with the central axis 114C of the protrusion 114.

[0078] A key 117 is provided protruding from the inner circumferential surface 116 of the other roller member 112. The key 117 of the other roller member 112 is positioned so that its central axis coincides with the central axis 115C of the recess 115.

[0079] Thus, the key 117 of one roller member 111 and the key 117 of the other roller member 112 are each positioned so as to be offset along the circumferential direction of the inner circumferential surface 116 by an angle θ formed by the central axis 114C of the convex portion 114 and the central axis 115C of the concave portion 115.

[0080] In this embodiment, the roller members 111 and 112 are formed by providing a protrusion 114 on the outer circumferential surface 113 of a ring-shaped member. Therefore, when applying a manufacturing method that involves removing the roller members 111 and 112 from a mold, they have a simple shape without undercuts, and can be manufactured at a lower cost compared to roller members with undercuts.

[0081] Furthermore, in the embodiment, the upper end surfaces of the protrusions 114 of the roller members 111 and 112 are parallel to the axis of rotation. However, in order to suppress the embossing material from being conveyed at an angle (skew), the upper end surfaces of the protrusions 114 of the roller members 111 and 112 may be configured to be inclined at a predetermined angle with respect to the axis of rotation. Moreover, in order to suppress skew, it is also possible to implement the upper end surfaces of the protrusions 114 of the roller members 111 and 112 with a shape or structure that is not a plane parallel to the axis of rotation, such as by providing grooves or other steps on the upper end surfaces of the protrusions 114.

[0082] Figure 5 is a perspective view showing how multiple roller members 111 and 112 are inserted along the axial direction of the first shaft 120U.

[0083] The arrangement of the multiple roller members 111 and 112 inserted along the axial direction of the second shaft 120D is the same as in Figure 5.

[0084] As shown in Figure 5, a first keyway 121U is formed in the first shaft 120U along the axial direction. The first keyway 121U is shaped to allow the keys 117 of the roller members 111 and 112 to be fitted into it.

[0085] Multiple roller members 111 and 112 are alternately inserted through shaft insertion holes 118 along the axial direction of the first shaft 120U. The multiple roller members 111 and 112 are inserted onto the first shaft 120U such that a key 117 fits into the first keyway 121U.

[0086] For example, 19 roller members 111 and 112 are alternately inserted onto the first shaft 120U.

[0087] The roller members 111 and 112, which are alternately inserted into the first shaft 120U, constitute the first roller 110U. The shaft insertion holes 118 of the roller members 111 and 112, which are alternately inserted into the first shaft 120U, are referred to as the first shaft insertion holes 118U. The key 117 of the roller members 111 and 112, which are fitted into the first keyway 121U of the first shaft 120U, are referred to as the first key 117U.

[0088] Similarly, a second keyway 121D is formed in the second shaft 120D along the axial direction. The second keyway 121D is shaped to allow the key 117 of the roller members 111 and 112 to be fitted into it.

[0089] Multiple roller members 111 and 112 are alternately inserted through shaft insertion holes 118 along the axial direction of the second shaft 120D. The multiple roller members 111 and 112 are inserted onto the second shaft 120D such that a key 117 fits into the second keyway 121D.

[0090] For example, 19 roller members 111 and 112 are alternately inserted onto the second shaft 120D.

[0091] The roller members 111 and 112, which are alternately inserted into the second shaft 120D, constitute the second roller 110D. The shaft insertion holes 118 of the roller members 111 and 112, which are alternately inserted into the second shaft 120D, are referred to as the second shaft insertion holes 118D. The keys 117 of the roller members 111 and 112, which are fitted into the second keyway 121D of the second shaft 120D, are referred to as the second key 117D.

[0092] For example, a total of 38 first rollers 110U, consisting of 19 roller members 111 and 19 roller members 112, are arranged along the rotation axis of the first shaft 120U. Similarly, a total of 38 second rollers 110D, consisting of 19 roller members 111 and 19 roller members 112, are arranged along the rotation axis of the second shaft 120D.

[0093] Figure 7 shows the first roller 110U and the second roller 110D arranged opposite each other, with the outer surface 113 facing forward. For the sake of explanation, Figure 7 shows the first roller 110U and the second roller 110D separately.

[0094] As shown by the dashed line in Figure 7, the protrusion 114 of one first roller 110U and the recess 115 of the other first roller 110U, which are adjacent to each other along the axial direction of the first shaft 120U, are arranged to be adjacent to each other along the axial direction. This corresponds to the fact that the first key 117U of one first roller 110U and the first key 117U of the other first roller 110U, which are adjacent to each other along the axial direction of the first shaft 120U, are projecting at positions offset along the circumferential direction of the inner circumferential surface 116.

[0095] Here, the distance D in the rotational axis direction between the protrusions 114, 114 of the two adjacent first rollers 110U, 110U along the rotational axis direction of the first shaft 120U is set to a predetermined distance such that the material to be embossed is embossed into a truncated square pyramidal shape, as will be described later. The distance D is defined by the width difference d between the width 113W of the outer circumferential surface 113 of the roller members 111, 112 and the width 114W of the protrusion 114.

[0096] Similarly, as shown by the dashed line, the protrusions 114 of one second roller 110D and the recesses 115 of the other second roller 110D, which are adjacent to each other along the axial direction of the second shaft 120D, are arranged to be adjacent to each other along the axial direction. This corresponds to the fact that the second keys 117D of one second roller 110D and the second keys 117D of the other second roller 110D, which are adjacent to each other along the axial direction of the second shaft 120D, are projecting from the inner circumferential surface 116 at offset positions along the circumferential direction.

[0097] Here, the distance D in the rotational axis direction between the protrusions 114, 114 of the two adjacent second rollers 110D, 110D along the rotational axis direction of the second shaft 120D is set to a predetermined distance such that the material to be embossed is embossed into a truncated square pyramidal shape, as will be described later. Also, the distance between the adjacent protrusions 114 of the first roller 110U and the second roller 110D is defined as distance L1. The following relationship holds between distance D, distance L1, and width 114W. L1 = 114W + 2D

[0098] Figure 6 is a side view of the first roller 110U and the second roller 110D in an opposing configuration. Figure 6 shows the insertion position of the material to be embossed 300' before embossing.

[0099] Figure 10 is a diagram corresponding to Figure 6, illustrating the shape of the emboss 301 formed by the first roller 110U and the second roller 110D.

[0100] As shown in Figures 6 and 10, the protrusions 114 of the second roller 110D and the recesses 115 between adjacent protrusions 114, 114 of the first roller 110U are spaced apart by a predetermined gap 114S, such that, in a side view of the second roller 110D and the first roller 110U, the material to be embossed 300' is embossed in a trapezoidal shape. Similarly, due to symmetry, the protrusions 114 of the first roller 110D and the recesses 115 between adjacent protrusions 114, 114 of the second roller 110D are spaced apart by a predetermined gap, such that, in a side view of the first roller 110U and the second roller 110D, the material to be embossed 300' is embossed in a trapezoidal shape.

[0101] In this embodiment, the relationship between the member on which the key is provided and the member on which the keyway is formed may be reversed.

[0102] In other words, a first key may be provided on the first shaft 120U along the axial direction, and a first key groove may be formed on the inner circumferential surface 116 of the first roller 110U into which the first key is fitted. In addition, a second key may be provided on the second shaft 120D along the axial direction, and a second key groove may be formed on the inner circumferential surface 116 of the second roller 110D into which the second key is fitted.

[0103] Furthermore, the first keyway of one first roller 110U and the first keyway of the other first roller 110U, which are adjacent to each other along the axial direction of the first shaft 120U, may be formed at positions offset along the circumferential direction of the inner circumferential surface 116, and the second keyway of one second roller 110D and the second keyway of the other second roller 110D, which are adjacent to each other along the axial direction of the second shaft 120D, may also be formed at positions offset along the circumferential direction of the inner circumferential surface 116.

[0104] (Embossed material 300)

[0105] Figure 8 shows the embossed material 300 being discharged from between the first roller 100U and the second roller 100D.

[0106] Figure 9 is a plan view showing the embossed material 300.

[0107] According to the embossing apparatus 200 of the embodiment, the embossed material 300 can be manufactured by inserting the material to be embossed 300' between a first roller 110U and a second roller 110D, which have intermittently protruding rectangular prism-shaped or truncated square pyramidal protrusions 114 along the circumferential direction of the outer surface 113.

[0108] The embossed material 300 produced by the embossing apparatus 200 of the embodiment has the following characteristics.

[0109] 1) The front surface has raised embossing 301 and the back surface has raised embossing 301, forming a checkerboard pattern when viewed from above.

[0110] 2) The convex embossing 301 is formed in the shape of a truncated square pyramid.

[0111] 3) The two adjacent convex embossed areas 301, 301 are connected by a wrinkled area 302.

[0112] 4) Compared to conventional embossed materials, the embossed surface has a more pronounced contrast, and there is no tearing that occurs during the embossing process.

[0113] Thus, with the embossing apparatus 200 of this embodiment, the contrast of the embossed surface can be enhanced compared to the conventional technology, and tearing that occurs during embossing can be suppressed.

[0114] Next, we will explain the relationship between the configuration of the embossing apparatus 200 in the embodiment and the characteristics of the embossing material 300.

[0115] As shown in Figure 8, the rotational direction side surface 301A of the emboss 301 formed on the embossed material 300 is tapered, and the rotational axis direction side surface 301B of the emboss 301 is also tapered, so that the emboss 301 as a whole is formed in a tapered truncated square pyramidal shape. As a result, tearing is less likely to occur around the emboss 301, and the unevenness of the surface is clearly defined.

[0116] (Tapered shape of the side surface 301A in the rotational direction of the embossed 301)

[0117] The formation of the tapered shape on the rotational side surface 301A of the emboss 301 can be explained by Figure 10.

[0118] The gap 114S between the protrusions 114 of the second roller 110D and the recesses 115 between the adjacent protrusions 114, 114 of the first roller 110U is formed in a trapezoidal shape. This trapezoidal gap 114S can be obtained by adjusting the number of protrusions 114 per roller (for example, 5). Because the gap 114S between the protrusions 114 of the second roller 110D and the recesses 115 between the adjacent protrusions 114, 114 of the first roller 110U is formed in a trapezoidal shape, the embossed surface 301 is less prone to tearing and has a distinct uneven surface. Similarly, due to symmetry, the gap 114S between the protrusions 114 of the first roller 110U and the recesses 115 between the adjacent protrusions 114, 114 of the second roller 110D is also formed in a trapezoidal shape.

[0119] (Tapered shape of the side surface 301B in the rotation axis direction of the embossed 301)

[0120] The formation of the tapered shape on the side surface 301B of the emboss 301 in the rotational axis direction can be explained by Figures 8 and 11.

[0121] As shown in Fig. 8, the distance D in the rotational axis direction between the convex portions 114, 114 of both adjacent first rollers 110U, 110U along the rotational axis direction of the first roller portion 100U is set to a predetermined distance such that the side surface 301B in the rotational axis direction of the emboss 301 is formed in a tapered shape with distinct concavities and convexities. However, the distance D is a value suppressed to such an extent that tearing does not occur due to shear stress. The same applies to the distance D in the rotational axis direction between the convex portions 114, 114 of both adjacent second rollers 110D, 110D along the rotational axis direction of the second roller portion 100D.

[0122] Figs. 11(A) and (B) are diagrams for explaining the shear stress generated in the embossed material 300 according to the distance D in the rotational axis direction between the convex portions 114, 114.

[0123] As shown in Fig. 11(A), when the distance D in the rotational axis direction between the convex portions 114, 114 is small, the shear stress P1 generated in the embossed material 300 according to the shear force F by the convex portions 114, 114 becomes large. When the distance D is small, the "play" around the emboss 301 is small with respect to the large shear stress P1, so the embossed material 300 is likely to tear.

[0124] On the other hand, as shown in Fig. 11(B), when the distance D in the rotational axis direction between the convex portions 114, 114 is large, the shear stress P2 (<P1) generated in the embossed material 300 according to the same shear force F by the convex portions 114, 114 becomes small. If the distance D is too large, the shear stress P2 becomes small, the "play" around the emboss 301 becomes large, and the distinctness of the concavities and convexities is lost, but tearing of the embossed material 300 is less likely to occur.

[0125] Therefore, it is desirable to set the distance D in the rotational axis direction between the convex portions 114, 114 to a value such that an emboss 301 that is not easily torn and has distinct concavities and convexities is formed.

[0126] The distance D in the rotational axis direction between the protrusions 114, 114 is defined by the width difference d between the width 113W of the outer circumferential surface 113 of the first roller 110U and the second roller 110D and the width 114W of the protrusion 114. For example, by setting the width 113W of the outer circumferential surface 113 to 11 mm and the width 114W of the protrusion 114 to 7 mm to 9 mm, and setting the width difference d to 2 mm to 4 mm, it was possible to manufacture an embossed material 300 in which an embossed surface 301 with a distinct relief of bumps and indentations was formed without any tearing.

[0127] Furthermore, the "play" around the embossed area 301 that occurs when the distance D becomes somewhat large manifests as wrinkles 302 in the embossed material 300. Since the two adjacent raised embossed areas 301, 301 are connected by the wrinkles 302, the occurrence of tearing is suppressed.

[0128] Furthermore, by increasing the distance D to a certain extent, the distortion of images such as characters and shapes printed on the embossed material 300 is reduced, and the visibility of images such as characters and shapes printed on the embossed material 300 is ensured.

[0129] Furthermore, the rounded (or chamfered) corners 114N and edges 114E of the roller protrusions 114 contribute to suppressing tearing of the embossed material 300. If the corners 114N and edges 114E of the protrusions 114 were not rounded (or chamfered), the shear stress would increase, making the embossed material 300 more prone to tearing. In addition, this tearing would cause greater distortion of the images such as letters and figures printed on the embossed material 300, degrading their visibility.

[0130] Figure 12 shows side views of the first and second rollers. As shown in Figure 12, the distance between adjacent protrusions 114 of the first and second rollers is defined as distance L2.

[0131] The simulation was conducted to simulate how the character image on the embossed material would be distorted when the embossed material 300, which had the character image shown in Figure 13 printed on it, was embossed, with the distance L1 of the protrusion 114 shown in Figure 7 and the distance L2 shown in Figure 12 set to 1.5 times the width 114W of the protrusion 114, and the step difference between the protrusion and recess of the roller set to 0.43 times the width 114W. Figure 14 shows the character image of the embossed material as viewed from above at this time. Furthermore, the simulation was conducted to simulate how the character image on the embossed material would be distorted when the embossed material 300, which had the character image shown in Figure 13 printed on it, was embossed, with the distances L1 and L2 set to 1.25 times the width 114W of the protrusion 114, and the step difference between the protrusion and recess of the roller set to 0.47 times the width 114W. Figure 15 shows the character image of the embossed material as viewed from above at this time. In Figures 14 and 15, the raised areas created by embossing are shown as solid rectangles, and the recessed areas are shown as dashed rectangles.

[0132] The character image shown in Figure 14 can be recognized without any problems when printed on embossed material, but the character image shown in Figure 15 is difficult to recognize when printed on embossed material. This is because making the distances L1 and L2 at least 1.5 times the width 114W of the protrusion 114 makes the slope of the embossed material, from the protrusion to the recess and from the recess to the protrusion, gentler, making it easier to recognize the character image printed on the slope. In other words, in order to recognize characters printed on embossed material without any problems, it is best to make the distances L1 and L2 of each protrusion 114 at least 1.5 times the width 114W of the protrusion 114. In the above simulation of distortion of character images due to embossing, the width of the emboss 114W was assumed to be the same length in the axial and circumferential directions of the roller. However, if the width differs in the rotational axis direction and the circumferential direction of the roller, the recognizability of images such as characters and figures printed on the embossed material can be maintained by setting the distance L1 to 1.5 times or more the width of the protrusion 114 in the rotational axis direction, and the distance L2 to 1.5 times or more the width of the protrusion 114 in the circumferential direction of the roller.

[0133] The embossing apparatus and embossing material of the embodiment can be modified, such as by omitting, adding, changing, or substituting components, within the scope described in the claims. [Industrial applicability]

[0134] This utility model is applicable to an embossing apparatus that creates cushioning material to protect articles from external impacts by embossing embossed materials such as kraft paper. [Explanation of Symbols]

[0135] 110U First Roller 110D The second Laura 113 Outer surface 114 Convex part 114S Gap 115 recess 200 Embossing machine

Claims

1. A first roller that is driven to rotate, A second roller is positioned opposite the first roller so that the material to be embossed can be inserted between it and the first roller, and is rotationally driven together with the first roller to emboss the material to be embossed. Equipped with, The first roller and the second roller are intermittently provided with convex portions in the shape of a rectangular prism or a truncated square pyramid along the circumferential direction of their outer surfaces for embossing. The adjacent protrusions of the first roller and the second roller are spaced apart by a certain distance from each other so that, when viewed from the side, the material to be embossed is embossed in a trapezoidal shape, so that images such as characters and figures printed on the material to be embossed can be recognized. Embossing machine.

2. Multiple first rollers are arranged along the axis of rotation, Multiple second rollers are arranged along the axis of rotation, The convex portion of one first roller and the concave portion of the other first roller, which are adjacent to each other along the axis of rotation, are arranged to be adjacent to each other along the axis of rotation, The convex portion of one second roller and the concave portion of the other second roller, which are adjacent to each other along the axis of rotation, are arranged to be adjacent to each other along the axis of rotation. The convex portions of the two first rollers adjacent to each other along the axis of rotation, The protrusions of the two adjacent second rollers along the axis of rotation are arranged at a second fixed distance apart so as to emboss the material to be embossed into a truncated square shape so that images such as characters and figures printed on the material to be embossed can be recognized. The embossing apparatus according to claim 1.

3. The first constant distance described in claim 1 is set to 1.5 times or more the circumferential width of the protrusions of the first roller and the second roller, The first and second rollers are configured to emboss the material to be embossed in a trapezoidal shape, as seen from a side view, so that images such as characters and figures printed on the material to be embossed can be recognized. The embossing apparatus according to claim 1.

4. The first constant distance described in claim 1 is set to be 1.5 times or more the circumferential width of the protrusions of the first roller and the second roller, The second constant distance described in claim 2 is set to be 1.5 times or more the axial width of the protrusions of the first roller and the second roller, The embossed material is configured to emboss the material into a truncated square shape so that images such as characters and figures printed on the material can be recognized. The embossing apparatus according to claim 2.

Images