Cutting device

Abstract

To provide a cutting device that is less prone to damage to the drive unit. [Solution] The cutting device 10 comprises a cutting blade 20a, a cutting blade 20b, and a pair of guide plates 50a and 50b. The pair of guide plates 50a and 50b are provided to sandwich the cutting blades 20a and 20b. The guide plates 50a and 50b are provided with recesses 51 that guide the movement of the object to be cut 90 between the cutting blades 20a and 20b. A narrow section 52 is provided in the middle part of the recess 51, in which the groove width is partially narrowed. A widened section 54 is provided in the part of the recess 51 from the narrow section 52 to the bottom surface, in which the groove width is wider than that of the narrow section 52.

Description

Technical Field

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

Background Art

[0002] Conventionally, there is a cutting device described in Patent Document 1 below. This cutting device includes a pair of cutting blades that sandwich and cut an object to be cut, a drive unit that operates the cutting blades by the driving force of an electric motor, and a guide plate provided so as to sandwich one of the cutting blades. A recess for guiding the object to be cut is formed in the guide plate between the pair of cutting blades.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the cutting device described in Patent Document 1, when one of the pair of cutting blades is damaged for some reason, an operator may use the cutting device without noticing it. In such a case, only the other cutting blade that is not damaged contacts the object to be cut, and the object to be cut is sandwiched between the other cutting blade and the guide plate, so that a reaction force acts only on the other cutting blade. When this reaction force is transmitted from the other cutting blade to the drive unit and an unintended uneven load is applied to the drive unit, the drive unit may be damaged.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to provide a cutting device in which it is difficult for the drive unit to be damaged.

Means for Solving the Problems

[0006] A cutting device that solves the above problems comprises a first cutting blade, a second cutting blade, a toggle link mechanism, a drive unit, and a pair of guide units. The first cutting blade is rotatably supported by a first shaft and has a blade forming portion at its tip. The second cutting blade is rotatably supported by a second shaft and has a blade forming portion at its tip. The toggle link mechanism has a first link member whose tip is rotatably connected to the base end of the first cutting blade, a second link member whose tip is rotatably connected to the base end of the second cutting blade, and a movable member rotatably connected to the base end of the first link member and the base end of the second link member. The drive unit opens and closes the first cutting blade and the second cutting blade via the first link member and the second link member by applying axial power to the movable member. The pair of guides are provided to clamp the first cutting blade and the second cutting blade in a direction perpendicular to the opening and closing direction. The guide section is formed to extend in a predetermined direction from the outer edge to the space between the blade-forming sections of the first and second cutting blades, and is provided with a recess that guides the movement of the object to be cut between the blade-forming sections of the first and second cutting blades. The middle portion of the recess is provided with a narrow section in which the groove width is partially narrowed. The portion of the recess from the narrow section to the bottom surface is provided with a widened section in which the groove width is wider than that of the narrow section.

[0007] With this configuration, if either the first or second cutting blade is damaged, the object to be cut, which is inserted into the recess, can escape from the narrow section to the wide section when it is caught between the other cutting blade and the guide section. This reduces the reaction force applied to the other cutting blade, and therefore reduces the reaction force transmitted from the other cutting blade to the drive unit. As a result, damage to the drive unit becomes less likely. [Effects of the Invention]

[0008] According to the cutting device of the present invention, damage to the drive unit is less likely to occur. [Brief explanation of the drawing]

[0009] [Figure 1] A perspective view showing the perspective structure of the cutting device according to the embodiment. [Figure 2]A cross-sectional view showing the partial fracture cross-sectional structure along line II-II in Figure 1. [Figure 3] A front view showing the front structure around the tip of the cutting device of the embodiment. [Figure 4] A cross-sectional view showing an example of the operation of the cutting device according to the embodiment. [Figure 5] A cross-sectional view showing an example of the operation of the cutting device according to the embodiment. [Figure 6] A front view showing the front structure around the tip of the cutting device of the embodiment. [Figure 7] A cross-sectional view showing an example of the operation of a cutting device as a reference. [Figure 8] A cross-sectional view showing an example of the operation of the cutting device according to the embodiment. [Figure 9] A cross-sectional view showing an example of the operation of the cutting device according to the embodiment. [Figure 10] A cross-sectional view showing an example of the arrangement of the cutting device according to the embodiment. [Figure 11] A front view showing the front structure around the tip of a cutting device of another embodiment. [Modes for carrying out the invention]

[0010] The following describes one embodiment of the cutting device with reference to the drawings. To facilitate understanding of the explanation, the same reference numerals are used for identical components in each drawing whenever possible, and redundant explanations are omitted.

[0011] <Embodiment> Figure 1 is a perspective view showing the oblique structure of the cutting device 10 of this embodiment. The cutting device 10 is an electric cutting device used, for example, to cut reinforcing bars that make up mesh reinforcement at a construction site. Figure 2 is a cross-sectional view showing the partially fractured cross-section structure along the line II-II in Figure 1.

[0012] As shown in FIG. 2, the cutting device 10 includes a pair of cutting blades 20a and 20b for cutting an object to be cut such as a reinforcing bar, a drive unit 30 that generates power for opening and closing the pair of cutting blades 20a and 20b, and a toggle link mechanism 40 that transmits the power of the drive unit 30 to the pair of cutting blades 20a and 20b. Further, as shown in FIG. 1, the cutting device 10 includes a pair of guide plates 50a and 50b provided adjacent to the pair of cutting blades 20a and 20b, respectively, and a housing 60 provided so as to surround the outer periphery of the drive unit 30.

[0013] As shown in FIG. 2, the cutting blade 20a is formed in a long plate shape, and the vicinity of its central portion is rotatably supported by a shaft portion 59a fixed to the main frame 70. The main frame 70 is fixed to the housing 60. A blade forming portion 21a is provided at the tip of the cutting blade 20a. As shown in FIG. 1, the blade forming portion 21a is arranged so as to be exposed to the outside from the tip of the housing 60. Similarly, the cutting blade 20b is also rotatably supported by a shaft portion 59b, and has a blade forming portion 21b at its tip. When the cutting blades 20a and 20b rotate about the shaft portions 59a and 59b as fulcrums, the respective blade forming portions 21a and 21b open and close in the Y direction in the figure. In the present embodiment, the Y direction is an example of the opening and closing direction. Further, the cutting blade 20a is an example of a first cutting blade, and the cutting blade 20b is an example of a second cutting blade. Furthermore, the shaft portion 59a is an example of a first shaft portion, and the shaft portion 59b is an example of a second shaft portion.

[0014] The toggle link mechanism 40 includes a pair of link members 41a and 41b, and a trunnion 42.

[0015] The link member 41a is formed in a plate shape. A shaft portion 410a is provided at the tip of the link member 41a. The base end portion of the cutting blade 20a is rotatably connected to the shaft portion 410a. Similarly, a shaft portion 410b to which the base end portion of the cutting blade 20b is rotatably connected is provided on the link member 41b. In the present embodiment, the link member 41a is an example of a first link member, and the link member 41b is an example of a second link member.

[0016] The trunion 42 is provided so as to be movable along a predetermined axis m10. In the present embodiment, the direction along the axis m10 is an example of the moving direction of the trunion 42. Hereinafter, the direction parallel to the axis m10 is referred to as the X direction. The X direction is a direction orthogonal to the Y direction. In the present embodiment, the X direction is an example of the predetermined direction. A shaft portion 420 is formed at the tip of the trunion 42. The base ends of the pair of link members 41a and 41b are rotatably connected to the shaft portion 420. The shaft portion 420 is inserted into a guide groove 71 of the main frame 70. The guide groove 71 is formed so as to extend along the axis m10. By guiding the shaft portion 420 by the guide groove 71 of the main frame 70, the trunion 42 is supported so as to be reciprocally movable in the X direction. The base end of the trunion 42 is formed in a cylindrical shape around the axis m10 and is connected to the drive unit 30. In the present embodiment, the trunion 42 is an example of the moving member.

[0017] The drive unit 30 opens and closes the cutting blades 20a and 20b via the link members 41a and 41b by applying power in the X direction (axial direction) to the trunion 42 of the toggle link mechanism 40. The drive unit 30 includes a ball screw mechanism 31, a reduction mechanism 32, and an electric motor 33.

[0018] The ball screw mechanism 31 includes a nut portion 310 and a screw portion 311.

[0019] The nut portion 310 is formed in a cylindrical shape around the axis m10 and has an internal thread portion on its inner peripheral surface. The tip of the nut portion 310 is inserted into and fixed inside the base end of the trunion 42 of the toggle link mechanism 40, thereby being integrally connected to the trunion 42.

[0020] The screw portion 311 is formed in a rod shape so as to extend along the axis m10 and has an external thread portion on its outer peripheral surface. The external thread portion of the screw portion 311 is screwed into the internal thread portion of the nut portion 310. The base end of the screw portion 311 is connected to the reduction mechanism 32.

[0021] The reduction mechanism 32 is connected to the output shaft of the electric motor 33. The reduction mechanism 32 reduces the rotation of the output shaft of the electric motor 33 and transmits it to the screw portion 311.

[0022] As shown in Figures 1 and 2, the cutting device 10 further includes an operating unit 80. When the operating unit 80 is turned ON by the operator, power is supplied to the electric motor 33, causing the electric motor 33 to rotate in the forward direction, which in turn causes the pair of cutting blades 20a and 20b to close. When the operating unit 80 is turned OFF by the operator, the electric motor 33 rotates in the reverse direction, causing the pair of cutting blades 20a and 20b to open, after which the power supply to the electric motor 33 is cut off.

[0023] As shown in Figure 1, the guide plates 50a and 50b are plate-shaped members provided so as to be exposed from the tip of the housing 60. The guide plates 50a and 50b are fixed to the main plate 70. The guide plates 50a and 50b are provided so as to sandwich the pair of cutting blades 20a and 20b in the Z direction. The Z direction is perpendicular to the X and Y directions. In this embodiment, the Z direction is an example of a direction perpendicular to the opening and closing direction of the cutting blades 20a and 20b. The guide plate 50a has a recess 51 formed therein that extends in the X direction from its outer edge to between the respective blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b. The guide plate 50b also has a similar recess 51 formed therein. The respective recesses 51 of the guide plates 50a and 50b are provided to guide the workpiece to be cut between the respective blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b. In this embodiment, guide plates 50a and 50b are examples of guide parts.

[0024] Next, an example of the operation of the cutting device 10 of this embodiment will be described. In the following, among the X directions, the direction from the drive unit 30 toward the cutting blades 20a and 20b, as shown in Figure 2, will be referred to as the Xa direction, and the opposite direction will be referred to as the Xb direction.

[0025] In the cutting device 10 of this embodiment, when the operating unit 80 is not being operated, the blade forming portions 21a and 21b of the pair of cutting blades 20a and 20b are positioned spaced apart in the Y direction, as shown in Figures 1 and 2.

[0026] When cutting an object using the cutting device 10, first, as shown in Figure 3, the object to be cut 90 is inserted into the respective recesses 51 of the guide plates 50a and 50b, positioning the object between the blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b. Next, when the operator operates the control unit 80, the electric motor 33 is driven, causing the output shaft of the electric motor 33 to rotate. The torque of this output shaft of the electric motor 33 is transmitted to the threaded portion 311 of the ball screw mechanism 31 via the reduction mechanism 32. As a result, when the threaded portion 311 rotates around the axis m10, the nut portion 310 is displaced in the Xa direction along the axis m10. Therefore, the trunnion 42 of the toggle link mechanism 40 is displaced in the Xa direction together with the nut portion 310. As a result of the displacement of the trunnion 42, the pair of link members 41a and 41b swing in the R1a and R1b directions, respectively, with the shaft portion 420 of the trunnion 42 as the pivot point, as shown in Figure 4. Therefore, the respective ends of the pair of link members 41a and 41b are displaced so that they are separated from each other in the Y direction. Due to this displacement of the pair of link members 41a and 41b, the pair of cutting blades 20a and 20b swing in the R2a and R2b directions, respectively, with the shaft portions 59a and 59b as the pivot points. As a result, the respective blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b are displaced so that they are closer to each other in the Y direction, and the object to be cut 90 is clamped between the respective blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b. As the blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b are further displaced so that they approach each other in the Y direction, the blade-forming portions 21a and 21b bite into the object to be cut 90. When the pair of cutting blades 20a and 20b are displaced to a position where the blade-forming portions 21a and 21b are closest to each other, as shown in Figure 5, the object to be cut 90 is cut by the blade-forming portions 21a and 21b.

[0027] After the blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b are closest together, the electric motor 33 rotates in reverse, causing the blade-forming portions 21a and 21b of the pair of cutting blades 20a and 20b to automatically return to the positions shown in Figures 1 and 2.

[0028] Next, the structure of the guide plates 50a and 50b of this embodiment will be described in detail. In the following description, the case in which the object to be cut 90 is a cylindrical member with a diameter D will be used as an example.

[0029] As shown in Figure 6, the recess 51 of the guide plate 50a has a shape that is symmetrical with respect to the axis m10. Hereinafter, the axis m10 will also be referred to as the central axis m10 of the recess 51. A narrow section 52 is provided in the middle part of the recess 51, in which the groove width is partially narrowed. The inner wall surface of the narrow section 52 is formed in a curved shape. The groove width H10 in the Y direction of the narrow section 52 is equal to or greater than the diameter D of the object to be cut 90. For example, if the diameter D of the object to be cut 90 is 8.6 mm, the groove width H10 in the Y direction of the narrow section 52 can be set to 9 mm. The narrow section 52 is provided at a position shifted by a predetermined distance L10 in the Y direction from the opening 56 of the recess 51. The predetermined distance L10 is longer than the radius D / 2 of the object to be cut 90 and shorter than 1.5D, which is 1.5 times the diameter of the object to be cut. The opening 56 of the recess 51 is chamfered.

[0030] In the recess 51 of the guide plate 50a, a widened section 54 is formed in the portion from the narrow section 52 to the bottom surface 53, with a groove width wider than that of the narrow section 52. The groove width H20 in the Y direction of the widened section 54 is equal to or greater than twice the diameter of the workpiece 90, or 2D. In the recess 51, the inner wall surface 55 from the narrow section 52 to the widened section 54 is tapered so that the groove width gradually widens from the narrow section 52 to the widened section 54.

[0031] A groove 58 is further formed on the bottom surface 53 of the recess 51. The groove 58 is formed in an arc shape with a radius of curvature equivalent to the radius D / 2 of the workpiece 90 to be cut. The groove 58 is positioned on the central axis m10 of the recess 51. The length L11 from the narrow portion 52 to the bottom surface 53 in the Y direction of the recess 51 is greater than or equal to the diameter D of the workpiece 90 to be cut.

[0032] The inner wall surface 57 of the recess 51 of the guide plate 50a, from the narrow portion 52 to the opening 56, is tapered such that the groove width gradually widens from the narrow portion 52 towards the opening 56. The angle θ that the inner wall surface 57 makes with the axis m10 is obtuse, i.e., less than 45 degrees.

[0033] Since the other guide plate 50b has the same shape as guide plate 50a, a detailed explanation of it will be omitted.

[0034] Next, an example of the operation of the cutting device 10 of this embodiment will be explained in comparison with the operation of the reference example cutting device 100 shown in Figure 7. In the reference example cutting device 100, the same reference numerals are used for components identical to those in the cutting device 10 of this embodiment, so redundant explanations will be omitted.

[0035] As shown in Figure 4, when the object to be cut 90 is cut by a pair of cutting blades 20a and 20b, reaction forces F1a and F1b are applied from the object to be cut 90 to each of the cutting blades 20a and 20b, as shown in the figure. As a result, forces F2a and F2b are applied to the link members 41a and 41b of the toggle link mechanism 40, as shown in Figure 4. At this time, the Y-direction component of force F2a and the Y-direction component of force F2b cancel each other out at the shaft portion 420 of the trunnion 42. Consequently, only the X-direction components of force F2a and force F2b are applied to the shaft portion 420 of the trunnion 42. In other words, only X-direction forces, or axial forces, are applied to the shaft portion 420 of the trunnion 42.

[0036] The cutting device 100 in the reference example shown in Figure 7 differs from the cutting device 10 of this embodiment in that a widened portion 54 is not formed in the recess 51; in other words, the portion from the narrowed portion 52 to the bottom surface 53 is formed with a constant groove width. In such a cutting device 100, if the cutting blade 20b is damaged, and the operator operates the control unit 80 without noticing the damage, only the cutting blade 20a may close. At this time, as shown in Figure 7, the object to be cut 90 will be sandwiched between the cutting blade 20a and the inner wall surface of the recess 51 of the guide plates 50a and 50b, so a reaction force F1a is applied only to the cutting blade 20a. In this case, only the force F2a shown in Figure 7 is applied to the shaft portion 420 of the trunnion 42. Therefore, not only the X-direction component of the force F2a but also the Y-direction component of the force F2a is applied to the shaft portion 420 of the trunnion 42. The Y-direction component of the force F2a applied to this shaft portion 420 acts on the ball screw mechanism 31 and the main frame 70, which may cause damage to them.

[0037] In this regard, in the cutting device 10 of this embodiment, as shown in Figure 8, when only the cutting blade 20a is in the closing operation, if the object to be cut 90 is located closer to the widening section 54 than to the narrow section 52, the object to be cut 90 is pushed by the cutting blade 20a and displaced so as to move away toward the widening section 54. Since the groove width H20 in the Y direction of the widening section 54 is equal to or greater than twice the diameter of the object to be cut 90, when the cutting blade 20a is displaced to the fully closed position as shown in Figure 8, a space S larger than the diameter D of the object to be cut is formed between the blade forming section 21a of the cutting blade 20a and the inner wall surfaces of the widening sections 54 of the guide plates 50a and 50b. As the object to be cut 90 is displaced to escape into this space S, it becomes less likely for the object to be cut 90 to be caught between the cutting blade 20a and the guide plates 50a and 50b. Therefore, compared to the cutting device 100 of the reference example shown in Figure 7, the reaction force applied to the cutting blade 20a is reduced. As a result, damage to the ball screw mechanism 31 and the main frame 70 becomes less likely.

[0038] On the other hand, as shown in Figure 9, if the object to be cut 90 is located closer to the opening 56 than the narrow section 52, the object to be cut 90 will be pushed by the cutting blade 20a and displaced to move away towards the opening 56. As a result, damage to the ball screw mechanism 31 and the main frame 70 becomes less likely.

[0039] Furthermore, if the object to be cut 90 is located in the narrow section 52, the object to be cut 90 will be displaced to escape toward the widened section 54 as shown in Figure 8, or to escape toward the opening 56 as shown in Figure 9, thus making it less likely for damage to occur to the ball screw mechanism 31 or the main frame 70.

[0040] Next, the operation and effects of the cutting device 10 of this embodiment will be described.

[0041] In the cutting device 10 of this embodiment, recesses 51 are formed in the guide plates 50a and 50b, respectively. The recesses 51 are formed to extend in the X direction from the outer edges of the guide plates 50a and 50b to the space between the blade forming portion 21a of the cutting blade 20a and the blade forming portion 21b of the cutting blade 20b, and guide the movement of the object to be cut 90 to the space between the blade forming portion 21a of the cutting blade 20a and the blade forming portion 21b of the cutting blade 20b. The portion of the recess 51 from the narrow portion 52 to the bottom surface 53 is provided with a widened portion 54, which has a groove width wider than the narrow portion 52.

[0042] With this configuration, even if either the cutting blade 20a or 20b is damaged, the reaction force applied to the other cutting blade can be reduced, thus reducing the reaction force transmitted from the other cutting blade to the drive unit 30. Therefore, damage to the drive unit 30 becomes less likely.

[0043] The groove width H10 of the narrow section 52 is equal in length to the diameter D of the object to be cut 90, or is equal to or greater than the diameter D of the object to be cut 90.

[0044] With this configuration, the object to be cut 90 can pass through the narrow section 52, making it possible to insert the object to be cut 90 into the widened section 54 more reliably.

[0045] The groove width H20 of the widened section 54 is equal to a length 2D which is twice the diameter of the object to be cut 90, or a length 2D or longer.

[0046] With this configuration, for example, when only the cutting blade 20a is operational and the cutting blade 20a is displaced to the fully closed position, a space S larger than the diameter D of the object to be cut 90 is formed between the blade forming portion 21a of the cutting blade 20a and the inner wall surface of the widening portion 54 of the guide plates 50a and 50b, as shown in Figure 8. By displacing the object to be cut 90 so as to escape into this space S, the reaction force applied to the cutting blade 20a can be reduced, making it even less likely for damage to occur to the ball screw mechanism 31 and the main frame 70.

[0047] In the recess 51, the inner wall surface 55 from the narrow section 52 to the wide section 54 is tapered so that the groove width gradually widens from the narrow section 52 to the wide section 54.

[0048] With this configuration, for example, as shown in Figure 8, when the object to be cut 90 is pushed by the cutting blade 20a and displaced to escape toward the widening section 54, the object to be cut 90 slides along the inner wall surface 55, allowing the object to be cut 90 to displace toward the widening section 54 more smoothly.

[0049] The length L11 of the recess 51 from the narrow portion 52 to the bottom surface 53 in the Y direction is greater than or equal to the diameter D of the workpiece 90 to be cut.

[0050] This configuration makes it possible to more reliably insert the object to be cut 90, which has passed through the narrow section 52, into the widened section 54.

[0051] The inner wall surface 57 of the recess 51 from the narrow portion 52 to the opening 56 is tapered so that the groove width gradually widens from the narrow portion 52 towards the opening 56.

[0052] With this configuration, the object to be cut 90 inserted through the opening 56 slides along the inner wall surface 57, allowing the object to be cut 90 to displace more smoothly toward the opening 56.

[0053] As shown in Figure 6, the narrow portion 52 is positioned at a predetermined distance L10 in the Y direction from the opening 56 of the recess 51. The predetermined distance L10 is longer than the radius D / 2 of the workpiece 90 to be cut, and shorter than a length of 1.5D which is 1.5 times the diameter of the workpiece to be cut.

[0054] With this configuration, as shown in Figure 10, when attempting to cut a structure 91 in which multiple objects to be cut are assembled in a grid pattern and placed on the ground G, for example, another object to be cut 91b, which is placed above the object to be cut 91a on the ground, can be positioned in the widening section 54. This allows, for example, if an attempt is made to cut object 91b while only the cutting blade 20a is operational, object 91b can be displaced to escape toward the widening section 54. Therefore, even when cutting a structure 91 as shown in Figure 10, damage to the drive unit 30 becomes less likely.

[0055] Furthermore, if an attempt is made to cut the object 91a placed on the ground, the object 91a will be positioned within the range from the opening 56 to the narrow section 52. Therefore, if an attempt is made to cut the object 91b while only the cutting blade 20a is operational in such a situation, the object 91a can be displaced to move away towards the opening 56. As a result, damage to the drive unit 30 is less likely to occur.

[0056] The inner wall surface of the narrow section 52 is formed in a curved shape.

[0057] With this configuration, even if the object to be cut 90 is located in the narrow section 52, when the object to be cut 90 is pushed by the cutting blade 20a, the object to be cut 90 is more likely to be displaced to either the widened section 54 or the opening 56, thus making it even less likely for damage to occur to the ball screw mechanism 31 or the main frame 70.

[0058] A groove 58 is formed on the bottom surface 53 of the recess 51. The groove 58 is formed in an arc shape with a radius of curvature equivalent to the radius D / 2 of the workpiece 90 to be cut. The groove 58 is positioned on the central axis m10 of the recess 51.

[0059] With this configuration, when the object to be cut 90 is inserted into the widened section 54 through the narrowed section 52, the object to be cut 90 enters the groove 58, thereby more reliably positioning the object to be cut 90 on the central axis m10 of the recess 51. Therefore, it becomes possible to cut the object to be cut 90 more appropriately with the cutting blades 20a and 20b.

[0060] <Other Embodiments> This disclosure is not limited to the specific examples given above.

[0061] For example, as shown in Figure 11, a groove 58 does not necessarily have to be formed on the bottom surface 53 of the recess 51. The length L12 from the narrow portion 52 to the bottom surface 53 in the Y direction of the recess 51 is greater than or equal to the diameter D of the workpiece 90 to be cut.

[0062] The groove width H20 in the Y direction of the widened section 54 can be set to any length as long as it is greater than the diameter D of the workpiece 90 to be cut. Even with this configuration, compared to the cutting device 100 of the reference example shown in Figure 7, the reaction force F1a applied to the cutting blade 20a is smaller, making it less likely for damage to occur to the ball screw mechanism 31 and the main frame 70.

[0063] The cutting device 10 may have only one of the guide plates 50a or 50b.

[0064] Even the above-mentioned examples, with appropriate design modifications by those skilled in the art, are included within the scope of this disclosure, as long as they possess the features of this disclosure. The elements, their arrangement, conditions, shapes, etc., of each of the above-mentioned examples are not limited to those exemplified and can be modified as appropriate. The elements of each of the above-mentioned examples can be combined in different ways as appropriate, as long as no technical inconsistencies arise. [Explanation of Symbols]

[0065] 10: Cutting device, 20a: Cutting blade (first cutting blade), 20b: Cutting blade (second cutting blade), 21a, 21b: Blade forming section, 30: Drive section, 40: Toggle link mechanism, 41a: Link member (first link member), 41b: Link member (second link member), 42: Trunnion (moving member), 50a, 50b: Guide plate (guide section), 51: Recess, 52: Narrow section, 54: Wide section, 55, 57: Inner wall surface, 56: Opening, 58: Groove section, 59a: Shaft section (first shaft section), 59b: Shaft section (second shaft section).

Claims

1. A first cutting blade is rotatably supported by a first shaft and has a blade-forming portion at its tip, A second cutting blade is rotatably supported by a second shaft and has a blade-forming portion at its tip, A toggle link mechanism having a first link member whose tip is rotatably connected to the base end of the first cutting blade, a second link member whose tip is rotatably connected to the base end of the second cutting blade, and movable members connected to the base end of the first link member and the base end of the second link member, A drive unit that opens and closes the first cutting blade and the second cutting blade via the first link member and the second link member by applying power to the moving member, The device comprises a pair of guide portions provided to clamp the first cutting blade and the second cutting blade in a direction perpendicular to the opening and closing direction, The guide portion is provided with a recess that extends in a predetermined direction from its outer edge to the space between the blade-forming portion of the first cutting blade and the blade-forming portion of the second cutting blade, and guides the movement of the object to be cut between the blade-forming portion of the first cutting blade and the blade-forming portion of the second cutting blade. In the middle portion of the recess, a narrow section is provided in which the groove width is partially narrowed. The portion of the recess from the narrow section to the bottom surface is provided with a widened section, the groove width of which is wider than that of the narrow section. Cutting device.

2. The groove width of the narrow portion is greater than or equal to the diameter of the object to be cut. The cutting device according to claim 1.

3. The groove width of the narrow portion is equal in length to the diameter of the object to be cut. The cutting device according to claim 1.

4. The width of the groove in the widened portion is greater than the diameter of the object to be cut. The cutting device according to claim 1.

5. The groove width of the widened portion is equivalent to a length equal to twice the diameter of the object to be cut. The cutting device according to claim 1.

6. The inner wall surface of the recess from the narrow portion to the wide portion is tapered such that the groove width gradually widens from the narrow portion towards the wide portion. The cutting device according to claim 1.

7. The length of the recess from the narrow portion to the bottom surface in the predetermined direction is greater than or equal to the diameter of the object to be cut. The cutting device according to claim 1.

8. A groove is formed on the bottom surface of the recess. The cutting device according to claim 1.

9. The groove is formed in an arc shape having a radius of curvature equal to the radius of the object to be cut. The cutting apparatus according to claim 8.

10. The inner wall surface of the recess from the narrow portion to the opening is tapered such that the groove width gradually widens from the narrow portion towards the opening. The cutting device according to claim 1.

11. The narrow portion is provided at a position offset by a predetermined distance in the predetermined direction from the opening of the recess, The predetermined distance is longer than the radius of the object to be cut, and shorter than 1.5 times the diameter of the object to be cut. The cutting device according to claim 1.

12. The inner wall surface of the narrow section is formed in a curved shape. The cutting device according to claim 1.

13. The widened portion has a shape that is symmetrical with respect to the central axis of the recess. The cutting device according to claim 1.

Images