Cutting device

Abstract

The present invention provides a cutting device that can suppress incomplete cutting of the object to be cut. [Solution] The cutting device 1 of the present invention comprises a mounting plate 9 having a mounting surface 13 on which a mortar molded object W is placed, and a cutting unit 15 that is movable relative to the mounting plate 9 and cuts the mortar molded object W on the mounting surface 13. The cutting unit 15 has a thread-like portion 25 and a frame 21 including a pair of holding portions 27, 29 that each hold both ends of the thread-like portion 25. The thread-like portion 25, which is stretched between the holding portions 27, 29, moves across the mortar molded object W to reach the mounting surface 13, thereby cutting the mortar molded object W. The mounting surface 13 is provided with holes 41 into which the tips of the holding portions 27 can be inserted in the direction of movement of the cutting unit 15.

Description

Technical Field

[0001] The present invention relates to a cutting device.

Background Art

[0002] Conventionally, there is known a device that places a cutting object on a predetermined placement surface and moves a cutting element toward the placement surface so as to cross the cutting object to cut the cutting object (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In this type of cutting device, if the cutting element does not reach the placement surface completely, the cutting object cannot be completely cut. However, for example, depending on the positional relationship between the cutting element and the holding portion that holds the cutting element, the holding portion may interfere with the placement surface before the cutting element, and the cutting element may not reach the placement surface completely. Further, for example, when the cutting element is a filamentous member, the cutting element is bent due to the cutting resistance. Then, even if both ends of the cutting element reach the placement surface, the vicinity of the center of the cutting element floats from the placement surface, and the vicinity of the center of the cutting object is not completely cut. Therefore, an object of the present invention is to provide a cutting device capable of suppressing incomplete cutting of a cutting object.

Means for Solving the Problems

[0005] The gist of the present invention resides in the following [1] to [3].

[0006] [1] A cutting device comprising: a mounting plate having a mounting surface on which an object to be cut is placed; and a cutting unit that is movable relative to the mounting plate and cuts the object to be cut on the mounting surface, wherein the cutting unit comprises a cutting element and a frame including a pair of cutting element holders that each hold both ends of the cutting element, and the cutting element, which is stretched between the cutting element holders, moves across the object to be cut to reach the mounting surface, thereby cutting the object to be cut, and the mounting surface is provided with holes into which the tips of the cutting element holders can be inserted in the direction of movement of the cutting unit.

[0007] [2] The cutting device according to [1], wherein the cutting element is a thread-like member stretched between the cutting element holding portions, and the portion of the cutting element holding portion from which the cutting element extends can be inserted into the hole beyond the surface described above.

[0008] [3] The cutting device according to [1] or [2], wherein the mounting surface is provided with a slit connected to the hole into which at least a portion of the cutting element can be inserted in the direction of movement of the cutting portion. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a cutting device that can suppress incomplete cutting of the object to be cut. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view of the cutting device according to the first embodiment. [Figure 2] This is a partial cross-sectional view of a cutting apparatus according to the first embodiment. [Figure 3] (a) is a cross-sectional view showing the state of a mortar sculpture during cutting, and (b) is a cross-sectional view showing the final stage of that cutting. [Figure 4] (a) and (b) are cross-sectional views showing various modified examples of the cutting device, respectively. [Figure 5] This is a perspective view of the cutting apparatus according to the second embodiment. [Figure 6] (a) is a cross-sectional view showing the final stage of cutting in a cutting apparatus according to the second embodiment, and (b) is a cross-sectional view showing a modified example of this cutting apparatus. [Figure 7] This is a perspective view of the cutting device according to the third embodiment. [Figure 8] (a) is a cross-sectional view showing the final stage of cutting in a cutting apparatus according to the third embodiment, and (b) is a cross-sectional view showing a modified example of this cutting apparatus. [Figure 9] (a) and (b) are perspective views showing modified blades in the cutting device according to the third embodiment, and (c) is a plan view illustrating the cutting conditions by the cutting device. [Modes for carrying out the invention]

[0011] [First Embodiment] The first embodiment of the cutting device according to the present invention will be described in detail below with reference to the drawings. Figure 1 is a perspective view of the cutting device 1, and Figure 2 is a partial cross-sectional view along the cut surface formed by the cutting device 1. In Figure 2, the mounting table 3, which will be described later, and the mortar molded object W placed on the mounting table 3 are shown in a cross-sectional view. The cutting device 1 cuts a mortar molded object W constructed with a 3D printer (not shown) in a vertical cross-section when it is in a semi-hardened state. The cutting device 1 of this embodiment is used, for example, to divide the mortar molded object W into multiple pieces of a transportable size. The mortar molded object W is divided into multiple pieces by the cutting device 1, and each piece is transported to the final installation site after hardening. Thereafter, at the final installation site, each piece is rearranged and installed according to the shape of the original mortar molded object W. It is not essential to join the ends of the installed pieces together, but the ends may be joined together with adhesive or the like.

[0012] In the following, the cross-section of the semi-hardened mortar structure W that is to be cut by the cutting device 1 will be referred to as the "planned cutting cross-section" and denoted as "Wa". In this embodiment, the height of the mortar structure W is, for example, about 50 cm, and the mortar structure W may be annular (for example, circular) in plan view, as illustrated in the figure. The horizontal width of the planned cutting cross-section Wa is, for example, 60 mm.

[0013] The cutting device 1 comprises a mounting table 3 for placing a mortar-formed object W, and a cutting unit 5 positioned near the mounting table 3. The mounting table 3 is placed on the horizontal upper surface 7a of the 3D printer's base plate 7. The mounting table 3 comprises a mounting plate 9 and legs 11. The mounting plate 9 is a rectangular flat plate, and its upper surface is a horizontal mounting surface 13 for placing a mortar-formed object W formed by the 3D printer. The legs 11 are positioned, for example, at each of the four corners of the mounting plate 9 and are inserted between the lower surface of the mounting plate 9 and the upper surface 7a of the base plate to support the mounting plate 9 by lifting it off the upper surface 7a of the base plate. In other words, the legs 11 function as spacers that form a gap between the mounting plate 9 and the upper surface 7a of the base plate. The height of the legs 11 is, for example, 100 mm. For example, a commercially available plywood (concrete panel) may be used as the mounting plate 9. For example, commercially available pallets may be used as the legs 11.

[0014] Such a mounting platform 3 is placed on the upper surface 7a of the 3D printer's base plate, and the nozzle (not shown) of the 3D printer moves planarly above the mounting surface 13, pushing out mortar, thereby forming a mortar layer on the mounting surface 13. A large number of such mortar layers are then stacked to construct a three-dimensional mortar object W on the mounting surface 13.

[0015] After the mortar-shaped object W as described above is constructed on the mounting table 3, the cutting unit 5 is installed in the vicinity of the mounting table 3 on the upper surface 7a of the surface plate of the 3D printer. The cutting unit 5 includes a cutting portion 15 that can move vertically in the vertical direction with respect to the mounting surface 13, and a pedestal portion 17 that supports the cutting portion 15 so as to be vertically movable. The cutting portion 15 includes a frame 21 and a filament portion 25 horizontally stretched at the lower end portion of the frame 21. The material of the frame 21 is not particularly limited, and for example, wood, plastic, metal, etc. can be appropriately adopted. The filament portion 25 functions as a cutting element for cutting the mortar-shaped object W. For example, a commercially available water thread may be used as the material of the filament portion 25. Also, as long as the required strength can be ensured, it is not limited to water thread, and nylon thread, steel wire, polyethylene thread, piano wire, wire, etc. may be used as the material of the filament portion 25.

[0016] The frame 21 has a pair of holding portions 27, 29 (cutting element holding portions) that respectively extend vertically and hold both ends of the filament portion 25, and a horizontal member 23 that connects the upper ends of the holding portions 27, 29. Among the pair of holding portions 27, 29, the side closer to the column portion 33 of the pedestal portion 17 described later is the holding portion 29, and the farther side is the holding portion 27. The upper end of the holding portion 27 and the upper end of the holding portion 29 are located at the same height as each other, and the lower end 27j of the holding portion 27 and the lower end 29j of the holding portion 29 are located at the same height as each other. In plan view, when the mortar-shaped object W forms an annular shape, one of the holding portions 27 is located inside the ring. Also, in plan view, the other holding portion 29 is located outside the mounting plate 9.

[0017] The frame 21 has a U-shape with an open lower end by including the holding parts 27, 29 and the horizontal member 23 as described above. A filamentous part 25 is horizontally spanned between the lower end parts of the holding parts 27, 29 and is stretched with a predetermined tension. Hereinafter, the part of the holding part 27 from which the filamentous part 25 extends (that is, the root part of the filamentous part 25 with respect to the holding part 27) is referred to as the "root part 27a". Similarly, the part of the holding part 29 from which the filamentous part 25 extends (that is, the root part of the filamentous part 25 with respect to the holding part 29) is referred to as the "root part 29a".

[0018] The pedestal part 17 includes a pedestal base 31 grounded on the upper surface 7a of the surface plate and a support part 33 rising vertically upward from an end of the pedestal base 31. The materials of the pedestal base 31 and the support part 33 are not particularly limited, and for example, wood, plastic, metal, etc. can be appropriately adopted. A guide rail 35 for guiding the vertical movement of the cutting part 15 is provided on the surface of the support part 33 on the side of the mounting table 3. The cutting part 15 is attached to the guide rail 35 and is integrally movable up and down guided by the guide rail 35.

[0019] The cutting operation of the mortar molded object W by the cutting device 1 as described above is performed while the mortar molded object W is in a semi-cured state after the construction of the mortar molded object W by the 3D printer. FIG. 3(a) is a cross-sectional view showing a state during the cutting of the mortar molded object W by the filamentous part 25, and FIG. 3(b) is a cross-sectional view showing the final stage of the cutting. In addition, in FIGS. 3(a) and 3(b), the illustration of the pedestal part 17 is omitted.

[0020] First, before the cutting operation begins, the cutting unit 5 is placed on the upper surface 7a of the base plate, as shown in Figures 1 and 2, in such a position that the thread-like portion 25 of the cutting section 15 is positioned above the planned cutting cross-section Wa of the mortar molded object W. Then, the user steps on the base base 31 of the base section 17 to fix and stabilize the cutting unit 5, and manually lowers the cutting section 15 vertically toward the mounting surface 13. As a result, as shown in Figure 3(a), the thread-like portion 25 of the cutting section 15 moves across the mortar molded object W to the mounting surface 13. Then, as shown in Figure 3(b), the mortar molded object W is cut using the trajectory of the thread-like portion 25 as the cutting surface. After that, the thread-like portion 25 is released from the frame 21 and removed without damaging the cutting surface. If the mortar structure W forms a ring when viewed from above, the mortar structure W is cut at a cross-section that opens the ring at one point.

[0021] Furthermore, in the cutting device 1 of this embodiment, a hole 41 is provided in the center of the mounting plate 9. The hole 41 is positioned vertically below the holding part 27, and the lower end of the holding part 27 can be inserted into the hole 41. If the mounting plate 9 does not have a hole 41, the following issues will occur. That is, if there is no hole 41, and the lower end 27j of the holding part 27 protrudes lower than the base 27a of the thread-like part 25, the lower end 27j of the holding part 27 will interfere with the mounting surface 13 before the thread-like part 25, which may prevent the thread-like part 25 from reaching the mounting surface 13 completely, resulting in an incomplete cutting of the mortar molded object W. Also, as the thread-like part 25 bites into the mortar molded object W, as shown in Figure 3(a), the cutting resistance causes the thread-like part 25 to bend upward. Even during the cutting process, the hardening of the mortar structure W due to the hydration reaction of cement continues, so the cutting resistance gradually increases, and the deflection described above tends to increase as the cutting progresses. If this deflection remains in the final stage of cutting, even if both ends of the filamentous part 25 reach the mounting surface 13, the area near the center of the filamentous part 25 will lift off the mounting surface 13, resulting in an incomplete cut of the mortar structure W.

[0022] As described above, if the cutting of the mortar molded object W is incomplete, post-processing is required, such as removing the thread material constituting the thread-like part 25 from the frame 21 and rubbing the thread material against the mounting surface 13 by hand to complete the cutting. Such post-processing makes the cutting work complicated. Furthermore, if the cut surface becomes rough due to the above-mentioned post-processing, repair work on the edges of the parts will be required afterward.

[0023] Therefore, in order to suppress the phenomenon of incomplete cutting of the mortar molded object W as described above, as shown in Figures 1 to 3, the cutting device 1 has a hole 41 in the center of the mounting plate 9. The hole 41 is, for example, circular in shape and is located in a position that does not overlap with the legs 11 of the mounting base 3 in a plan view, and penetrates the mounting plate 9 in the thickness direction (vertically). The hole 41 is also located in a position that does not overlap with the mortar molded object W in a plan view. In a plan view, the planned cutting cross section Wa of the mortar molded object W exists between the hole 41 and the outer edge of the mounting plate 9. In a plan view, if the mortar molded object W is annular, the hole 41 is located inside the annulus. Such a hole 41 may be provided in the mounting plate 9 in advance before the construction of the mortar molded object W by the 3D printer.

[0024] As described above, the hole 41 is located vertically below the holding portion 27 and is larger than the lower end of the holding portion 27. Therefore, during the cutting operation, as shown in Figure 3(b), the lower end 27j of the holding portion 27 can be inserted into the hole 41 in the direction of its movement (vertically downward) and can be removed in the opposite direction. In this case, the lower end 27j of the holding portion 27 can penetrate through the hole 41 to a position below the mounting surface 13, for example, into the space between the mounting plate 9 and the upper surface 7a of the base plate.

[0025] The final stage of cutting by such a cutting device 1 is as follows: In the final stage of cutting, as shown in Figure 3(b), the lower end 27j of the holding part 27 is inserted into the hole 41 and penetrates to a position lower than the mounting surface 13. Similarly, the lower end 29j of the holding part 29 penetrates to a position lower than the mounting surface 13 on the outside of the mounting plate 9. Then, by the user pushing the cutting part 15 further downward, the base 27a of the filamentous part 25 of the holding part 27 is inserted deep into the hole 41 and penetrates to a position lower than the mounting surface 13. Similarly, the base 29a of the filamentous part 25 of the holding part 29 penetrates to a position lower than the mounting surface 13 on the outside of the mounting plate 9. Furthermore, in order for the base portions 27a and 29a to penetrate to a position lower than the mounting surface 13, the height difference between the lower end 27j of the holding portion 27 and the base portion 27a, and the height difference between the lower end 29j of the holding portion 29 and the base portion 29a, should be set to be smaller than the height difference between the upper surface 7a of the base plate and the mounting surface 13.

[0026] As described above, when the base portions 27a and 29a penetrate to a position lower than the mounting surface 13 in the final stage of cutting, the filamentous portion 25 deforms so as to bend at the edge of the hole 41 and the outer edge of the mounting plate 9, and the filamentous portion 25 is pressed against the mounting surface 13 at this bent corner. In addition, the force that the user exerts by pushing the cutting portion 15 downward is transmitted to the filamentous portion 25, and the tension on the filamentous portion 25 increases. Then, the increased tension on the filamentous portion 25 reduces the deflection of the filamentous portion 25 as described above (see Figure 3(a)), and the cutting of the mortar molded object W at the center of the filamentous portion 25 progresses further. Ideally, as shown in Figure 3(b), the filamentous portion 25 extends completely in a straight line on the mounting surface 13 between the bent corner portions, and the entire filamentous portion 25 reaches the mounting surface 13 completely, cutting the mortar molded object W to its lower end.

[0027] As described above, with the cutting device 1, interference between the lower end 27j of the holding part 27 and the mounting surface 13 is avoided, and this interference prevents the descent of the thread-like part 25 from being hindered. Furthermore, even if some deflection of the thread-like part 25 (see Figure 3(a)) remains in the final stage of cutting, the remaining deflection is reduced, and the mortar molded object W can be cut to a position close to the lower end. In other words, with the cutting device 1, incomplete cutting of the mortar molded object W can be suppressed.

[0028] In the above example, hole 41 is a through hole that penetrates the mounting plate 9, but as shown in Figure 4(a), hole 41 may be a bottomed hole as long as it has sufficient depth to allow the base portion 27a to be inserted to a position lower than the mounting surface 13. Also, in the above example, the retaining portion 29 is positioned outside the mounting plate 9 in a plan view, but as shown in Figure 4(b), the retaining portion 29 may be positioned above the mounting plate 9. In this case, the mounting plate 9 may have a hole 42 positioned vertically below the retaining portion 29 into which the lower end 29j and the base portion 29a of the retaining portion 29 can be inserted, similar to hole 41.

[0029] Another method for dividing the mortar sculpture W is to use a plate-shaped member with vertical width instead of the filamentous part 25 as a cutting element. However, in this case, the friction between the cutting element and the cut surface is large, so the cut surface tends to be rough. Also, when removing the cutting element after the cutting is complete, it is necessary to lift the cutting element again along the cut surface, and this action also tends to roughen the cut surface. Another method for dividing the mortar sculpture W is to cut it using a cutting tool (e.g., a power tool) after the mortar sculpture W has hardened. However, in this case, there is a risk that the mortar sculpture W will crack or the cut surface will chip. Also, when cutting with a cutting tool, the calf fray is large, so the gap between the ends of the pieces that will be rearranged at the final installation site will be large. In addition, dust is generated during cutting, so the working environment deteriorates.

[0030] In contrast, the method used in this embodiment, in which the mortar molded object W is cut with the filamentous portion 25 when it is in a semi-hardened state, can solve the above-mentioned problems. Furthermore, since roughness of the cut surface is suppressed, there is no need for processing such as repairing the edges of the pieces, and the aesthetics are also superior. In addition, it is safer compared to cutting with a cutting tool.

[0031] [Second Embodiment] Next, a second embodiment of the cutting device according to the present invention will be described in detail. Figure 5 is a perspective view of the cutting device 201. The cutting device 201 further includes a slit 51 provided in the mounting plate 9, in addition to the cutting device 1 of the first embodiment. The other configurations are the same as in the first embodiment, so the same or equivalent components are denoted by the same reference numerals as in the first embodiment, and redundant explanations are omitted.

[0032] The slit 51 extends linearly through the mounting plate 9 and penetrates the mounting plate 9 in the thickness direction. One end of the slit 51 is connected to the hole 41, and the other end of the slit 51 reaches the outer edge of the mounting plate 9. In other words, the slit 51 is cut out so as to connect from the outer edge of the mounting plate 9 to the hole 41. In a plan view, the thread-like portion 25 is positioned to overlap with the slit 51.

[0033] In the final stage of cutting by such a cutting device 201, as shown in Figure 6(a), the lower end 27j and the base portion 27a of the holding portion 27 are inserted into the hole 41 and penetrate to a position lower than the mounting surface 13. The filamentous portion 25 also passes completely through the interior of the mortar molded object W and is inserted into the slit 51, penetrating to a position lower than the mounting surface 13, and extending linearly between the base portions 27a and 29a. For example, the filamentous portion 25 penetrates the space between the mounting plate 9 and the upper surface 7a of the base plate.

[0034] As described above, with the cutting device 201 equipped with the slit 51, the filamentous portion 25 can penetrate to a position lower than the mounting surface 13, so the filamentous portion 25 can completely pass through the inside of the mortar molded object W and cut to its lower end. In other words, the cutting device 201 can suppress incomplete cutting of the mortar molded object W.

[0035] In the example above, the slit 51 penetrates the mounting plate 9 in the thickness direction. However, as shown in Figure 6(b), for example, the slit 51 may be a closed-bottom slit (groove) as long as it has sufficient depth to allow the filamentous portion 25 to be inserted to a position below the mounting surface 13. Alternatively, the width of the slit 51 may be made the same as the diameter of the hole 41 so that the contours of the slit 51 and the hole 41 are seamlessly continuous.

[0036] [Third Embodiment] Next, a third embodiment of the cutting device according to the present invention will be described in detail. Figure 7 is a perspective view of the cutting device 301. The cutting device 301 is equipped with a blade 26 as a cutting element for cutting the mortar molded object W, instead of the filamentous part 25 in the cutting device 1 of the first embodiment. The other configurations are the same as in the first embodiment, so the same or equivalent components are denoted by the same reference numerals as in the first embodiment and redundant explanations are omitted.

[0037] The blade 26 is a thin, plate-like steel member that has width in the vertical direction and is horizontally stretched between the lower ends of the holding parts 27 and 29. The lower edge of the blade 26 extends horizontally and functions as a cutting edge 26a for cutting the mortar molded object W. The lower end 27j of the holding part 27 protrudes slightly below the cutting edge 26a. In such a cutting device 301, if there is no hole 41, the lower end 27j of the holding part 27 may interfere with the mounting surface 13 before the cutting edge 26a, potentially preventing the cutting edge 26a from fully reaching the mounting surface 13 and resulting in an incomplete cut of the mortar molded object W.

[0038] In contrast, since the cutting device 301 is equipped with a hole 41, in the final stage of the cutting operation, as shown in Figure 8(a), the lower end 27j of the holding part 27 can be inserted into the hole 41 and penetrate to a position lower than the mounting surface 13. The lower end 27j of the holding part 27 can penetrate, for example, into the space between the mounting plate 9 and the upper surface 7a of the base plate. The blade 26a then reaches the mounting surface 13, and the mortar molded object W is cut to its lower end by the blade 26a. Therefore, the cutting device 301 can suppress incomplete cutting of the mortar molded object W. In order for the blade 26a to reach the mounting surface 13, the height difference between the lower end 27j of the holding part 27 and the blade 26a should be set to be smaller than the height difference between the upper surface 7a of the base plate and the mounting surface 13.

[0039] Furthermore, the cutting device 301 may also include a slit 51 similar to that of the cutting device 201 of the second embodiment (Figure 5). In this case, as shown in Figure 8(b), at least the lower edge of the blade 26, the cutting portion 26a, can be inserted into the slit 51 and penetrate to a position lower than the mounting surface 13. The lower end 27j of the holding portion 27 and the cutting portion 26a can penetrate, for example, the space between the mounting plate 9 and the upper surface 7a of the base plate. Therefore, the cutting portion 26a of the blade 26 can completely pass through the inside of the mortar molded object W and cut the mortar molded object W to its lower end. In the example of Figure 8(b), in the final stage of cutting, only the cutting portion 26a at the lower end of the blade 26 is inserted into the slit 51, but the entire blade 26 may be inserted into the slit 51. Also, the hole 41 may be a bottomed hole, and the slit 51 may be a bottomed slit (see Figure 6(b)).

[0040] Furthermore, although the blade 26 in the example in Figure 7 is a flat plate-shaped member, a blade that forms a V shape in plan view, as shown in Figure 9(a), or a blade that forms a U shape in plan view, as shown in Figure 9(b), may be used instead. In addition, a blade that forms an even more complex shape (for example, a wave shape) in plan view may be used. In this case, the ends of the cut pieces will be non-linear, such as V-shaped or U-shaped, in plan view. In this case, when the pieces are rearranged at the final installation site, the outside and inside of the ring of the mortar molded object W can not be seen through the gaps between the ends of the pieces, and as a result, the traces of cutting are less noticeable. Also, since the ends form a V-shape, U-shape, etc. in plan view, it becomes easier to distinguish adjacent pieces when rearranging the pieces at the final installation site. Furthermore, if the ends of adjacent pieces are bonded together, the bonding area increases compared to straight ends, so the bonding strength between the pieces increases.

[0041] The present invention can be implemented in various forms, including the embodiments described above, by making various changes and improvements based on the knowledge of those skilled in the art. Furthermore, it is possible to construct modified versions by utilizing the technical matters described in the embodiments described above. The configurations of each embodiment may be used in appropriate combinations.

[0042] The cutting devices 1,201,301 of each embodiment are particularly suitable for use under the following cutting condition C1. Figure 9(c) is a plan view showing an example of a mounting surface 13 and a mortar molded object W to illustrate the cutting condition C1. <Cutting Condition C1> In a plan view, the straight line L extending from the planned cutting cross-section Wa of the mortar molded object W intersects the mortar molded object W on the mounting surface 13 at locations other than the planned cutting cross-section Wa.

[0043] As an example of a condition that meets the above cutting condition C1, in the cutting devices 1,201 and 301 of each embodiment, the planned cutting surface Wa is such that the mortar molded object W forms an annular shape in plan view, and the annular shape is opened at one point (see Figure 1, etc.).

[0044] Under such cutting conditions C1, if the cutting elements 25 and 26 are arranged to span the entire mounting surface 13 in a plan view, the mortar molded object W will be cut not only at the planned cutting cross-section Wa but also at other locations (for example, the cutting surface Wb in Figure 9(c)). Therefore, in order to avoid this, in the cutting devices 1,201 and 301 of each embodiment, at least one of the holding parts 27 and 29 (holding part 27 in each embodiment) is positioned on the mounting surface 13 in a plan view. However, in that case, when the cutting part 15 is lowered, the lower end 27j of the holding part 27 interferes with the mounting surface 13, and this interference may prevent the cutting element from completely reaching the mounting surface 13, potentially resulting in an incomplete cut of the mortar molded object W. Thus, in order to solve the problems that may occur under the above cutting conditions C1, the cutting devices 1,201 and 301 are designed to allow the cutting part 15 to descend sufficiently by providing a hole 41 in the mounting surface 13. In the cutting device 1,201,301, the holding portion 27 and the hole 41 are arranged on a straight line L in a plan view.

[0045] Furthermore, if the cutting elements 25 and 26 are arranged to span the entire mounting surface 13 in a plan view, the cutting section 15 becomes larger, worsening the operability of the cutting operation. Also, in the case of the cutting device 1,201, the filamentous portion 25 becomes longer, so the deflection of the filamentous portion 25 due to cutting resistance also increases. In comparison, with a configuration in which at least one of the holding portions 27 and 29 is positioned on the mounting surface 13 in a plan view, the distance between the holding portions 27 and 29 can be brought closer to the width of the planned cutting cross section Wa, and the length of the filamentous portion 25 can be brought closer to the minimum necessary length. By making the filamentous portion 25 as short as possible in this way, the deflection of the filamentous portion 25 due to cutting resistance is reduced.

[0046] Furthermore, the cutting devices 1,201,301 may be applied when the above cutting condition C1 is not met. Also, the object to be cut by the cutting devices 1,201,301 is not limited to annular shapes, and the shape of the object to be cut is not restricted. In addition, although a semi-hardened mortar molded object W was described as an example of the object to be cut in the above embodiment, the material of the object to be cut in the cutting device of the present invention is not restricted. Various plastic materials, including a semi-hardened mortar molded object W, can be the object to be cut by the cutting device of the present invention. Moreover, for example, the present invention can be applied to cutting devices for objects made of resin, metal, etc. [Explanation of symbols]

[0047] 1, 201, 301... Cutting device, 9... Mounting plate, 13... Mounting surface, 15... Cutting section, 21... Frame, 25... Thread-like section (cutting element, thread-like member), 26... Blade (cutting element), 27, 29... Holding section (cutting element holding section), 27a, 29a... Base section, 27j, 29j... Lower end, 51... Slit, W... Mortar molded object (object to be cut).

Claims

1. A mounting plate having a mounting surface on which the object to be cut is placed, A cutting device comprising a cutting section that is movable relative to the mounting plate and cuts the object to be cut on the mounting surface described above, The aforementioned cut portion is The device comprises a cutting element and a frame including a pair of cutting element holders that each hold both ends of the cutting element, and cuts the object to be cut by moving the cutting element, which is stretched between the cutting element holders, across the object to be cut and reaching the aforementioned surface. A cutting device wherein the mounting surface is provided with a hole into which the tip of the cutting element holding part can be inserted in the direction of movement of the cutting part.

2. The cutting element is a thread-like member stretched between the cutting element holding portions, The cutting device according to claim 1, wherein the portion of the cutting element holding portion from which the cutting element extends can be inserted into the hole to a depth greater than the aforementioned mounting surface.

3. The cutting device according to claim 1, wherein the mounting surface is provided with a slit connected to the hole into which at least a portion of the cutting element can be inserted in the direction of movement of the cutting portion.

Images