JP7769191B2 - Sawing device and sawing method - Google Patents

Description

This disclosure relates to a sawing device and a sawing method.

Patent Document 1 discloses a method for cutting structural steel, consisting of any one of H-beam, I-beam, angle steel, and channel steel, using a rotating circular saw blade to eliminate or reduce the generation of cutting burrs. The method involves making a groove-shaped cut along a cutting line in the structural steel from the front side, and then cutting the cut-lined structural steel from the back side along the cutting line.

Japanese Patent Application Laid-Open No. 2008-246666

This disclosure provides a sawing method that is effective in suppressing burrs.

A sawing method according to one aspect of the present disclosure is a method for sawing a workpiece with a blade having sawtooth edges, and includes forming a cut groove in the workpiece by driving the blade in a first cutting mode so that the sawtooth edges that have cut the workpiece immediately exit the workpiece, and sawing the workpiece by driving the blade in a second cutting mode so that the sawtooth edges that have cut the workpiece exit the workpiece via the cut groove.

When cutting in the first mode results in sawing the workpiece, the uncut portion, which has become thinner in the final stage of cutting, may be pulled by the saw teeth and escape outside the workpiece, leaving behind a burr. On the other hand, when cutting in the second mode results in sawing the workpiece, the saw teeth act to pull the uncut portion into the cut groove, preventing the uncut portion from escaping outside the workpiece until it is sawn. For this reason, a sawing method that forms a cut groove in the first mode and then saws the workpiece in the second mode is effective in reducing burrs.

The method may further include transitioning from first mode cutting to second mode cutting while the blade is positioned within the cut groove. If the blade is moved out of the cut groove during the transition from first mode cutting to second mode cutting, chipping of the workpiece is likely to occur when the blade re-enters the cut groove. A sawing method in which first mode cutting is transitioned to second mode cutting while the blade is positioned in the cut groove can further reduce chipping of the workpiece. Furthermore, by keeping the blade within the cut groove, the movement of the blade required to transition from first mode cutting to second mode cutting is reduced, making this sawing method also effective in shortening sawing time and reducing the footprint of the device.

In the first mode of cutting, the saw blades that cut the workpiece enter the workpiece from the second surface of the workpiece and cut the workpiece until they exit the workpiece from the first surface. In the second mode of cutting, the saw blades may transition from entering the workpiece from the second surface and exiting the workpiece via the cut groove to entering the workpiece from the first surface and exiting the workpiece via the cut groove. In this case, the cutting period in the second mode can be extended to further suppress burrs.

A sawing device according to another aspect of the present disclosure includes a blade having sawtooth edges, a drive unit for driving the blade, a first cutting control unit for controlling the drive unit to form a cut groove in the workpiece by driving the blade in a first mode of cutting so that the sawtooth cuts the workpiece and immediately exits the workpiece, a second cutting control unit for controlling the drive unit to saw the workpiece in a second mode of cutting so that the sawtooth cuts the workpiece and exits the workpiece through the cut groove, and a transition control unit for controlling the drive unit to transition from the first mode of cutting to the second mode of cutting while the blade remains within the cut groove. This sawing device makes it possible to easily suppress burrs in the first mode of cutting and the second mode of cutting with high reproducibility.

The drive device includes a rotation drive unit that rotates the blade about a rotation axis that passes through the center of the periphery so as to circulate the sawtooth in a first circulation direction along the periphery; a first displacement drive unit that moves the blade along a first traveling direction perpendicular to the rotation axis; and a second displacement drive unit that moves the blade along a second traveling direction that is perpendicular to the rotation axis and intersects the first traveling direction. The first cutting control unit may move the blade using at least the first displacement drive unit in the first mode of cutting, and the second cutting control unit may move the blade using at least the second displacement drive unit in the second mode of cutting. In this case, burrs produced in the first mode of cutting and the second mode of cutting can be easily suppressed using a simple configuration that combines the first displacement drive unit and the second variable drive unit.

This disclosure provides a sawing method that is effective in suppressing burrs.

FIG. 2 is a schematic diagram illustrating the configuration of a sawing device. FIG. FIG. 10 is a cross-sectional view illustrating the configuration of a second displacement driving unit. 10 is a cross-sectional view illustrating the configuration of a height adjustment unit. FIG. FIG. 10 is a schematic diagram illustrating a first mode of cutting. FIG. 10 is a schematic diagram illustrating a transition from cutting in a first mode to cutting in a second mode. FIG. 10 is a schematic diagram illustrating the state immediately after the start of cutting in the second mode. FIG. 10 is a schematic diagram illustrating a state immediately before completion of cutting in a second mode. 10 is a schematic diagram illustrating a case where sawing cannot be completed in cutting in the second mode because the cutting range in the first mode is inappropriate; FIG. 10 is a schematic diagram illustrating a case where sawing cannot be completed in cutting in the second mode because the cutting range in the first mode is inappropriate; FIG . 10 is a schematic diagram illustrating a case where sawing cannot be completed in cutting in the second mode because the cutting range in the first mode is inappropriate; FIG . FIG. 2 is a block diagram illustrating a hardware configuration of a controller. 10 is a flowchart illustrating a sawing procedure.

Embodiments will be described in detail below with reference to the drawings. In the description, identical elements or elements with identical functions will be assigned the same reference numerals, and duplicate descriptions will be omitted.

[Sawing device]
The sawing device 1 shown in Fig. 1 is a device for sawing long steel materials. Specific examples of the steel materials include shaped steel such as round steel and square steel. The sawing device 1 has a blade 10, a drive unit 20, and a controller 100.

The blade 10 has sawtooth 11 on its periphery 12. For example, the blade 10 has a disk shape and the periphery 12 is circular. The blade 10 may have multiple sawtooth 11 arranged along its periphery (see Figure 2).

The drive unit 20 drives the blade 10. For example, the drive unit 20 has a movable support base 30, a fixed support base 40, a rotation drive unit 50, a first displacement drive unit 60, a second displacement drive unit 70, and a height change unit 80.

The rotational drive unit 50 rotates the blade 10 around a rotational axis 51 passing through the center of the periphery 12 so as to circulate the sawtooth 11 in a first circulation direction RD1 along the periphery 12. For example, the rotational drive unit 50 rotates the blade 10 around the rotational axis 51 that is perpendicular to the blade 10 at the center of the periphery 12. As an example, the rotational drive unit 50 rotates the blade 10 around the rotational axis 51 using an electric rotary actuator.

The movable support base 30 supports the rotation drive unit 50 and the blade 10 so that the rotation axis 51 is horizontal. Therefore, the rotation drive unit 50 rotates the blade 10 around the horizontal rotation axis 51. The fixed support base 40 supports the movable support base 30 so that it can be displaced along a first direction of travel MD1 that is perpendicular to the rotation axis 51. For example, the fixed support base 40 supports the movable support base 30 so that it can be displaced along the horizontal first direction of travel MD1.

For ease of explanation, the first traveling direction MD1 will be referred to as the front-to-rear direction of the sawing device 1. The blade 10 is positioned near the front end of the movable support base 30. The work support base 90 is positioned in front of the fixed support base 40. The work support base 90 supports the workpiece 91 to be sawed. When the movable support base 30 advances relative to the fixed support base 40, the blade 10 advances relative to the workpiece 91. When the movable support base 30 retreats relative to the fixed support base 40, the blade 10 retreats relative to the workpiece 91.

The fixed support base 40 has a plurality of support rollers 41. The plurality of support rollers 41 includes at least two support rollers 41 arranged in a front-to-rear arrangement. Each of the plurality of support rollers 41 is rotatable about a rotation axis 42 parallel to the rotation axis 51. The support rollers 41 are rotatable about the rotation axis 51, allowing the movable support base 30 to be displaced along the first traveling direction MD1.

The first displacement drive unit 60 moves the blade 10 along the first traveling direction MD1. For example, the first displacement drive unit 60 has an advance/retract actuator 61. The advance/retract actuator 61 is provided on the fixed support base 40 so as to displace the movable support base 30 along the first traveling direction MD1. A specific example of the advance/retract actuator 61 is a hydraulic cylinder, but is not limited to this. For example, the advance/retract actuator 61 may be an electric linear actuator.

The second displacement drive unit 70 moves the blade 10 along a second traveling direction MD2 that is perpendicular to the rotation axis 51 and intersects the first traveling direction MD1. For example, the second displacement drive unit 70 raises and lowers the blade 10 along the second traveling direction MD2 that intersects the horizontal plane. As an example, the second displacement drive unit 70 raises and lowers the blade 10 along the second traveling direction MD2 that is perpendicular (vertical) to the horizontal plane. Note that the second traveling direction MD2 that intersects the horizontal plane is not limited to the vertical second traveling direction MD2. The second displacement drive unit 70 may also be configured to raise and lower the blade 10 along a second traveling direction MD2 that is inclined with respect to the vertical direction.

For example, the sawing device 1 includes multiple second displacement drive units 70 corresponding to the multiple support rollers 41, respectively. Each of the multiple second displacement drive units 70 raises and lowers the corresponding support roller 41. As the support roller 41 rises and lowers, the movable support base 30 rises and lowers, and the blade 10 supported by the movable support base 30 also rises and lowers.

Each of the multiple second displacement drive units 70 has a lifting rotation shaft 71 and a lifting actuator 72, as shown in FIG. 3, for example. The lifting rotation shaft 71 is fixed to the rotation shaft 42 of the support roller 41 and extends parallel to the rotation shaft 42. The central axis 74 of the lifting rotation shaft 71 is spaced apart from the central axis 43 of the rotation shaft 42. The lifting actuator 72 is, for example, an electric or hydraulic rotary actuator, and rotates the lifting rotation shaft 71 about its central axis 74. Because the central axis 74 of the lifting rotation shaft 71 is spaced apart from the central axis 43 of the rotation shaft 42, rotation of the lifting rotation shaft 71 about the central axis 74 raises and lowers the central axis 43 of the rotation shaft 42.

The second displacement drive unit 70 may be configured in any manner as long as it can move the movable support base 30 at the required stroke. For example, the second displacement drive unit 70 may be an electric linear actuator that raises and lowers the support roller 41, or a hydraulic cylinder that raises and lowers the support roller 41.

The height change unit 80 changes the height of the blade 10 during cutting in the first mode. The height change unit 80 may be configured to raise and lower the second displacement drive unit 70. This allows the second displacement drive unit 70 to raise and lower the height set by the height change unit 80.

As shown in FIG. 4, the height change unit 80 includes a plurality of lower wedges 81, a slide spacer 82, and a slide actuator 83. The plurality of lower wedges 81 correspond to the plurality of second displacement drive units 70, respectively. Each of the plurality of lower wedges 81 is provided below the corresponding second displacement drive unit 70 and has an upper surface 84 that gradually becomes higher from front to rear. The slide spacer 82 is interposed between the plurality of lower wedges 81 and the plurality of second displacement drive units 70. A plurality of upper wedges 85 that correspond to the plurality of lower wedges 81, respectively, are provided below the slide spacer 82. Each of the plurality of upper wedges 85 has a lower surface 86 that gradually becomes higher from front to rear. The lower surface 86 contacts the upper surface 84 of the corresponding lower wedge 81.

The slide actuator 83 is, for example, a hydraulic cylinder, and slides the slide spacer 82 in the front-to-rear direction. When the slide actuator 83 slides the slide spacer 82 rearward, each of the multiple upper wedges 85 slides up the upper surface 84 of the lower wedge 81 and rises. In response, the second displacement drive unit 70 above the upper wedge 85 rises. When the slide actuator 83 slides the slide spacer 82 forward, each of the multiple upper wedges 85 slides down the upper surface 84 of the lower wedge 81 and descends. In response, the second displacement drive unit 70 above the upper wedge 85 descends.

The height change unit 80 may be configured in any way as long as it can change the height of the blade 10. For example, the height change unit 80 may be configured to slide the slide spacer 82 using an electric linear actuator. Alternatively, the height change unit 80 may be configured to directly raise and lower the second displacement drive unit 70 using a hydraulic cylinder or an electric linear actuator, without using the slide spacer 82.

The controller 100 controls the drive unit 20. When the workpiece 91 is sawed in the first mode cutting described above, the uncut portion, which has become thin in the final stage of cutting, may be pulled by the saw teeth 11 and escape outside the workpiece 91, leaving behind a burr. On the other hand, when the workpiece 91 is sawed in the second mode cutting, the saw teeth 11 act to pull the uncut portion into the cut groove, preventing the uncut portion from escaping outside the workpiece 91 until it is sawed. Therefore, the controller 100 is configured to control the drive unit 20 to form a cut groove in the workpiece 91 by cutting in the first mode described above, and to control the drive unit 20 to saw the workpiece 91 by cutting in the second mode described above. This makes it possible to prevent burrs from being generated when the workpiece 91 is sawed.

As shown in FIG. 1, the controller 100 has, as its functional configuration (hereinafter referred to as "functional blocks"), a first cutting control unit 111, a second cutting control unit 112, and a transition control unit 113. The first cutting control unit 111 controls the drive unit 20 to form a cut groove in the workpiece 91 by cutting in a first mode, which drives the blade 10 so that the sawtooth 11, which has cut the workpiece 91, immediately exits the workpiece 91. The sawtooth 11, which has cut the workpiece 91, immediately exits the workpiece 91, meaning that the trajectory of the sawtooth 11, which moves from inside the workpiece 91 to outside the workpiece 91, penetrates into the uncut portion of the workpiece 91 until it reaches the outer surface of the workpiece 91.

In the first mode of cutting, the first cutting control unit 111 controls the drive unit 20 to move the blade 10 while circulating the saw teeth 11 in a first circulation direction RD1 along the periphery 12. For example, the first cutting control unit 111 controls the rotation drive unit 50 to rotate the blade 10 around a rotation axis 51 passing through the center of the periphery 12 in order to circulate the saw teeth 11 in the first circulation direction RD1.

In the first mode of cutting, the first cutting control unit 111 controls the drive unit 20 to move the blade 10 along the first direction of travel MD1. The first cutting control unit 111 controls the drive unit 20 to move the blade 10 while positioning the rotation axis 51 on a first line ML1 that is along the first direction of travel MD1 and away from the workpiece 91. In this case, the first cutting control unit 111 positions the rotation axis 51 on the first line ML1 that is defined so that the entire cross section of the workpiece 91 falls within the movement range of the blade 10.

As an example, the first cutting control unit 111 controls the drive device 20 to advance the blade 10 along the horizontal first traveling direction MD1. For example, the first cutting control unit 111 moves the movable support base 30 using the first displacement drive unit 60, thereby moving the blade 10 along the first traveling direction MD1. The first cutting control unit 111 controls the drive device 20 to advance the blade 10 with the rotation axis 51 positioned above the workpiece 91 and the lower end of the blade 10 positioned below the lower end of the workpiece 91. For example, the height of the blade 10 is adjusted by the height change unit 80 so that the rotation axis 51 is positioned above the workpiece 91 and the lower end of the blade 10 is positioned below the lower end of the workpiece 91, and the movable support base 30 is advanced by the first displacement drive unit 60.

When the rotation axis 51 is located above the workpiece 91 and the lower end of the blade 10 is located below the underside of the workpiece 91, the above-mentioned first line ML1 is located above the workpiece 91, and the entire cross section of the workpiece 91 is within the movement range of the blade 10. When the first line ML1 is located above the workpiece 91, the first cutting control unit 111 controls the rotation drive unit 50 to circulate the saw teeth 11 in a first circulation direction RD1 in which the saw teeth 11 that cut the workpiece 91 descend. For example, the first cutting control unit 111 controls the rotation drive unit 50 to circulate the saw teeth 11 in the first circulation direction RD1 in which the front saw teeth 11 descend and the rear saw teeth 11 ascend.

The second cutting control unit 112 controls the drive unit 20 to saw the workpiece 91 using a second cutting mode in which the blade 10 is driven so that the saw blade 10, having cut the workpiece 91, passes through the cut groove and exits the workpiece 91. "Sawing" means that the workpiece 91 is divided into two pieces by cutting with the saw blade 11. "The saw blade 11, having cut the workpiece 91, passes through the cut groove and exits the workpiece 91" means that the trajectory of the saw blade 11 that moves from inside the workpiece 91 to outside the workpiece 91 passes through the uncut portion and then passes through the cut groove before reaching the outer surface of the workpiece 91.

The first cutting control unit 111 may complete cutting in the first mode by cutting the workpiece 91 until the saw blade 11 that cuts the workpiece 91 extends from the first surface of the workpiece 91 to the outside of the workpiece 91. In this case, the second cutting control unit 112 controls the drive unit 20 so that, in cutting in the second mode, the sawing of the workpiece 91 is completed when the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the first surface. The first cutting control unit 111 may complete cutting in the first mode by cutting the workpiece 91 until the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the second surface of the workpiece 91 and extends from the first surface of the workpiece 91 to the outside of the workpiece 91. In this case, the second cutting control unit 112 controls the drive unit 20 so that, in cutting in the second mode, the saw blades 11 that cut the workpiece 91 transition from a state in which they enter the workpiece 91 from the second surface and exit the workpiece 91 through the cut groove to a state in which they enter the workpiece 91 from the first surface and exit the workpiece 91 through the cut groove.

Even during cutting in the second mode, the second cutting control unit 112 controls the drive unit 20 to move the blade 10 while circulating the saw teeth 11 in the first circulation direction RD1. For example, the second cutting control unit 112 controls the rotation drive unit 50 to rotate the blade 10 around the rotation axis 51 passing through the center of the periphery 12 in order to circulate the saw teeth 11 in the first circulation direction RD1.

The second cutting control unit 112 may control the drive unit 20 to move the blade 10 along a second traveling direction MD2 that intersects the first traveling direction MD1 during cutting in the second mode. For example, the first cutting control unit 111 controls the drive unit 20 to advance the blade 10 along the horizontal first traveling direction MD1 during part of cutting in the first mode. The second cutting control unit 112 controls the drive unit 20 to move the blade 10 along a second traveling direction MD2 that intersects a horizontal plane during part of cutting in the second mode. As an example, the second cutting control unit 112 raises and lowers the movable support table 30 using the second displacement drive unit 70 during cutting in the second mode.

The transition control unit 113 controls the drive unit 20 to transition from cutting in the first mode to cutting in the second mode while the blade 10 remains in the cut groove. The transition control unit 113 also controls the drive unit 20 to move the blade 10 while circulating the sawtooth 11 in the first circulation direction RD1 during the transition period from the first mode to the second mode (hereinafter simply referred to as the "transition period"). For example, the transition control unit 113 controls the rotation drive unit 50 to rotate the blade 10 around the rotation axis 51 passing through the center of the periphery 12 in order to circulate the sawtooth 11 in the first circulation direction RD1.

During the transition period, the transition control unit 113 causes the drive unit 20 to move the blade 10 so as to bypass the uncut portion of the workpiece 91. During the transition period, the transition control unit 113 moves the blade 10 until a second line ML2, which runs along the second traveling direction MD2 and passes through the rotation axis 51, passes through the uncut portion of the workpiece 91. When the transition control unit 113 completes the movement of the blade 10, the position of the second line ML2 is determined. During second-mode cutting, the second cutting control unit 112 controls the drive unit 20 to move the blade 10 while positioning the rotation axis 51 on the second line ML2. The transition control unit 113 may determine the second line ML2 at a position where the entire cross-section of the workpiece 91 is within the movement range of the blade 10 during second-mode cutting.

The transition control unit 113 controls the drive unit 20 to move the blade 10 while continuing to cut the remaining uncut portion of the workpiece 91 with the saw teeth 11, even during the transition period. For example, the transition control unit 113 controls the drive unit 20 to move the blade 10 along a trajectory that gradually cuts the saw teeth 11 into the remaining uncut portion during the transition period.

For example, if the first cutting control unit 111 controls the drive unit 20 to advance the blade 10 along the horizontal first advancement direction MD1 during cutting in the first mode, the transition control unit 113 controls the drive unit 20 during the transition period to further advance the blade 10 while bypassing the uncut portion of the workpiece 91 in an upward direction. In this case, the second cutting control unit 112 may control the drive unit 20 to lower the blade 10 along the second advancement direction MD2 during cutting in the second mode.

As an example, during the transition period, the transition control unit 113 may raise the movable support base 30 using the second displacement drive unit 70 and advance the movable support base 30 using the first displacement drive unit 60. As a result, the blade 10 rises and advances during the transition period. After the ascent period in which the second displacement drive unit 70 raises the movable support base 30, the transition control unit 113 advances the movable support base 30 using the first displacement drive unit 60. The transition control unit 113 at least partially overlaps the ascent period in which the second displacement drive unit 70 raises the movable support base 30 and the advance period in which the first displacement drive unit 60 advances the movable support base 30. During the overlapping period between the ascent period and the advance period, the movable support base 30 advances diagonally upward.

The following provides more specific examples of the first-mode cutting, the transition from first-mode cutting to second-mode cutting, and second-mode cutting that the first cutting control unit 111, second cutting control unit 112, and transition control unit 113 cause the drive unit 20 to perform. Figure 5 is a schematic diagram illustrating first-mode cutting. In Figure 5, the workpiece 91 has a generally rectangular cross-sectional shape and includes a first surface 92 facing downward, a second surface 93 facing forward, a third surface 94 facing upward, and a fourth surface 95 facing rearward. The height of the blade 10 is determined so that the rotation axis 51 is positioned above the workpiece 91 and the lower end of the blade 10 is positioned below the lower surface (first surface 92) of the workpiece 91. At the start of first-mode cutting, the sawtooth 11 cuts the portion where the third surface 94 and the fourth surface 95 intersect, forming a cut groove 96. Thereafter, as the blade 10 advances, cutting in the first mode transitions to a state in which the saw teeth 11 cutting the workpiece 91 enter the workpiece 91 from the third surface 94 and exit the workpiece 91 from the fourth surface 95. Further thereafter, cutting in the first mode transitions to a state in which the saw teeth 11 cutting the workpiece 91 enter the workpiece 91 from the second surface 93 and exit the workpiece 91 from the first surface 92, as shown in FIG. 5.

Figure 6 is a schematic diagram illustrating the transition from first-mode cutting to second-mode cutting. The transition control unit 113 raises the blade 10 using the second displacement drive unit 70 and advances the blade 10 using the first displacement drive unit 60 so that the blade 10 bypasses the uncut portion 97 of the workpiece 91. As shown in Figure 6, the transition control unit 113 advances the blade 10 diagonally upward using the combination of the second displacement drive unit 70 and the first displacement drive unit 60. The transition control unit 113 also advances the blade 10 along a curved trajectory that bypasses the uncut portion 97 using the combination of the second displacement drive unit 70 and the first displacement drive unit 60. The transition control unit 113 advances the blade 10 until a second line ML2 that runs along the vertical second direction of travel MD2 and passes through the rotation axis 51 passes through the uncut portion 97 (see Figure 7).

Figure 7 is a schematic diagram illustrating the state immediately after the start of second-mode cutting. The second cutting control unit 112 lowers the blade 10 using the second displacement drive unit 70. This starts second-mode cutting. At the start of second-mode cutting, the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the second surface 93, cuts the uncut portion 97, and then exits the workpiece 91 through the cut groove 96.

Then, as the blade 10 descends, the second mode of cutting transitions to a state in which the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the first surface 92, cuts the uncut portion 97, and then exits the workpiece 91 through the cut groove 96. Figure 8 is a schematic diagram illustrating the state just before the completion of second mode cutting. As is clear from Figure 8, the state in which the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the first surface 92, cuts the uncut portion 97, and then exits the workpiece 91 through the cut groove 96 is maintained until the workpiece 91 is sawn (until the entire uncut portion 97 is cut).

Referring to Figures 9, 10, and 11, we also illustrate a case where sawing cannot be completed in second mode cutting because the cutting range in first mode is inappropriate. Figure 9 illustrates first mode cutting. In Figure 9, the height of the blade 10 is set so that the bottom end of the blade 10 is positioned above the bottom surface (first surface 92) of the workpiece 91. In this state, the first cutting control unit 111 advances the blade 10 using the first displacement drive unit 60, thereby forming a cut groove 96 in the top of the workpiece 91 and an uncut portion 97 in the bottom of the workpiece 91.

Figure 10 illustrates an example of transitioning from first-mode cutting to second-mode cutting. As shown in Figure 10, the transition control unit 113 lowers the blade 10 using the second displacement drive unit 70. This transition transitions from first-mode cutting to second-mode cutting. When the transition is complete, the saw blade 11 that cuts the workpiece 91 enters the workpiece 91 from the first surface 92, cuts the uncut portion 97, and then exits the workpiece 91 through the cut groove 96.

After the transition is complete, the second cutting control unit 112 retracts the blade 10 using the first displacement drive unit 60. Thereafter, cutting in the second mode continues, but as the saw blade 11 cutting the workpiece 91 approaches the fourth surface 95, as shown in FIG. 11 , cutting in the second mode reverts to cutting in the first mode. In cutting in the first mode, the saw blade 11 that has cut the workpiece 91 immediately moves out of the workpiece 91 from the fourth surface 95. In this way, because cutting in the second mode reverts to cutting in the first mode before sawing the workpiece 91, in the example shown in FIGS. 9, 10, and 11, it is not possible to saw the workpiece 91 in cutting in the second mode.

The above provides specific examples of first mode cutting, the transition from first mode cutting to second mode cutting, and second mode cutting, but the direction of movement of the blade 10 during each period is merely an example.

The controller 100 may be further configured to adjust the height of the blade 10 using the height change unit 80. For example, as shown in FIG. 1, the controller 100 further includes a height adjustment unit 114 as a functional block. For example, the height adjustment unit 114 may control the height change unit 80 to adjust the height of the blade 10 to a target height input to an input device 196 (described below).

The height adjustment unit 114 may automatically set a target height based on the outer diameter of the blade 10 and control the height change unit 80 to adjust the height of the blade 10 to the set target height. In this case, the sawing device 1 may further include an outer diameter sensor 52 that detects the outer diameter of the blade 10, and the height adjustment unit 114 may automatically set the target height based on the detection results of the outer diameter sensor 52.

Figure 12 is a block diagram illustrating the hardware configuration of the controller 100. As shown in Figure 12, the controller 100 includes a circuit 190. The circuit 190 includes one or more processors 191, memory 192, storage 193, input/output ports 194, a display device 195, and an input device 196.

Storage 193 stores a program that causes controller 100 to control drive unit 20 to form a cut groove in workpiece 91 by cutting in the first mode, and to control drive unit 20 to saw workpiece 91 by cutting in the second mode. For example, storage 193 stores a program that causes controller 100 to configure each of the functional blocks described above.

Memory 192 temporarily stores programs loaded from storage 193. One or more processors 191 execute the programs stored in memory 192 and configure the functional blocks described above. The one or more processors 191 also store intermediate calculation results generated during program execution in memory 192 as appropriate, and refer to these results in subsequent processing.

The input/output port 194 inputs and outputs information between the rotation drive unit 50, first displacement drive unit 60, second displacement drive unit 70, height change unit 80, and outer diameter sensor 52 in response to requests from one or more processors 191. The display device 195 displays information to the operator. Specific examples of the display device 195 include an LCD monitor. The input device 196 acquires input from the operator. Specific examples of the input device 196 include a mouse and a keyboard. The input device 196 may be integrated with the display device 195 as a so-called touch panel. The display device 195 and input device 196 may be connected to one or more processors 191 via a network line such as the Internet.

The hardware configuration of the controller 100 shown above is merely an example and can be modified as appropriate. For example, at least some of the functional blocks may be configured using dedicated logic circuit elements such as an ASIC (Application Specific Integrated Circuit) rather than one or more processors 191.

[Sawing method]
Next, as an example of a sawing method, a control procedure executed by the controller 100 will be illustrated. This procedure includes controlling the drive device 20 to form a cut groove in the workpiece 91 by cutting in the first mode, and controlling the drive device 20 to saw the workpiece 91 by cutting in the second mode.

As shown in FIG. 13, the controller 100 first executes steps S01 and S02. In step S01, the height adjustment unit 114 adjusts the height of the blade 10 in the first mode of cutting using the height change unit 80. In step S02, the first cutting control unit 111 starts rotating the blade 10 using the rotation drive unit 50 so as to circulate the sawtooth 11 in the first circulation direction RD1.

Next, the controller 100 executes steps S03, S04, and S05. In step S03, the first cutting control unit 111 advances the rotating blade 10 using the first displacement drive unit 60, thereby forming a cut groove in the workpiece 91 through first-mode cutting. In step S04, the transition control unit 113 transitions from first-mode cutting to second-mode cutting by moving the blade 10 using the second displacement drive unit 70 and the first displacement drive unit 60 so as to bypass the uncut portion 97 upward. In step S05, the second cutting control unit 112 lowers the blade 10 using the second displacement drive unit 70, thereby sawing the workpiece 91 through second-mode cutting.

Next, the controller 100 executes steps S06 and S07. In step S06, the second cutting control unit 112 controls the second displacement drive unit 70 and the first displacement drive unit 60 to return the blade 10 to the position it was in before the start of step S03. In step S07, the rotation drive unit 50 stops the rotation of the blade 10. This completes sawing of the workpiece 91 through first mode cutting and second mode cutting. Note that while the procedure for a single sawing location has been exemplified, if there are multiple sawing locations, steps S03 to S06 may be repeated until all sawing locations have been sawed before step S07.

[Effects of this embodiment]
The sawing method using the sawing device 1 described above is a method of sawing a workpiece with a blade 10 having saw teeth 11 on its periphery 12, and includes forming a notch in the workpiece by cutting in a first mode in which the blade 10 is driven so that the saw teeth 11 that have cut the workpiece immediately exit the workpiece, and sawing the workpiece by cutting in a second mode in which the blade 10 is driven so that the saw teeth 11 that have cut the workpiece exit the workpiece through the notch.

When cutting in the first mode results in sawing the workpiece, the uncut portion, which has become thinner in the final stage of cutting, may be pulled by the saw teeth 11 and escape outside the workpiece, leaving behind a burr. On the other hand, when cutting in the second mode results in sawing the workpiece, the saw teeth 11 act to pull the uncut portion into the cut groove, preventing the uncut portion from escaping outside the workpiece until it is sawn. For this reason, a sawing method in which a cut groove is formed in the first mode of cutting and the workpiece is sawn in the second mode of cutting is effective in preventing burrs.

The method may further include transitioning from the first mode cutting to the second mode cutting while the blade 10 is positioned within the cut groove. If the blade 10 is moved out of the cut groove during the transition from the first mode cutting to the second mode cutting, chipping of the workpiece is likely to occur when the blade 10 re-enters the cut groove. A sawing method in which the first mode cutting is transitioned to the second mode cutting while the blade 10 is positioned in the cut groove can further reduce chipping of the workpiece. Furthermore, by keeping the blade 10 within the cut groove, the movement of the blade 10 required to transition from the first mode cutting to the second mode cutting is reduced, making this sawing method also effective in shortening the sawing time.

In the first mode of cutting, the saw teeth 11 that cut the workpiece enter the workpiece from the second surface of the workpiece and cut the workpiece until they exit the workpiece from the first surface. In the second mode of cutting, the saw teeth 11 that cut the workpiece may transition from entering the workpiece from the second surface and exiting the workpiece via the cut groove to entering the workpiece from the first surface and exiting the workpiece via the cut groove. In this case, the cutting period in the second mode can be extended to further suppress burrs.

The sawing device 1 includes a blade 10 having sawtooth edges 11 on its periphery 12, a drive unit 20 that drives the blade 10, a first cutting control unit that controls the drive unit 20 to form a cut groove in the workpiece by driving the blade 10 in a first cutting mode so that the sawtooth edges 11 immediately exit the workpiece after cutting the workpiece, a second cutting control unit that controls the drive unit 20 to saw the workpiece by driving the blade 10 in a second cutting mode so that the sawtooth edges 11 exit the workpiece after cutting the workpiece through the cut groove, and a transition control unit that controls the drive unit 20 to transition from the first cutting mode to the second cutting mode while the blade 10 remains in the cut groove. This sawing device 1 makes it easy to suppress burrs in the first and second cutting modes with high reproducibility.

The drive unit 20 includes a rotation drive unit 50 that rotates the blade 10 about a rotation axis passing through the center of the periphery 12 so as to circulate the saw teeth 11 in a first circulation direction RD1 along the periphery 12; a first displacement drive unit 60 that moves the blade 10 along a first forward direction MD1 perpendicular to the rotation axis; and a second displacement drive unit 70 that moves the blade 10 along a second forward direction MD2 perpendicular to the rotation axis and intersecting the first forward direction MD1. The first cutting control unit may move the blade 10 using the first displacement drive unit 60 in the first mode of cutting, and the second cutting control unit may move the blade 10 using the second displacement drive unit 70 in the second mode of cutting. In this case, a simple configuration combining the first displacement drive unit 60 and the second displacement drive unit can easily suppress burrs in both the first and second mode of cutting.

Although the embodiments have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the invention.

1...sawing device, 10...blade, 11...sawtooth, 12...periphery, 20...drive device, 50...rotation drive unit, RD1...first circulation direction, MD1...first travel direction, MD2...second travel direction, 60...first displacement drive unit, ML1...first line, 70...second displacement drive unit, ML2...second line, 80...height change unit.

Claims (4)

A method for sawing a workpiece with a blade having sawtooth on its periphery, comprising:
forming a cut groove in the workpiece by cutting in a first mode in which the blade is driven so that the sawtooth that has cut the workpiece immediately exits the workpiece;
sawing the workpiece by a second mode of cutting in which the blade is driven so that the saw blade that has cut the workpiece passes through the cutting groove and exits the workpiece;
The workpiece has a second surface where the saw blades that cut the workpiece enter the workpiece in the first cutting mode, and a first surface where the saw blades that entered the workpiece exit the workpiece,
In the second mode of cutting, the saw blades that cut the workpiece transition from a state in which they enter the workpiece from the second surface at the end of cutting in the first mode and exit the workpiece through the cut groove to a state in which they enter the workpiece from the first surface at the end of cutting in the first mode and exit the workpiece through the cut groove. The sawing method of claim 1, further comprising transitioning from the first mode of cutting to the second mode of cutting while the blade is positioned within the cut groove. a blade having sawtooth on its periphery;
a drive device that drives the blade;
a first cutting control unit that controls the drive device to form a notch in the workpiece by cutting in a first mode that drives the blade so that the sawtooth that has cut the workpiece immediately moves out of the workpiece;
a second cutting control unit that controls the drive device to saw the workpiece by a second mode of cutting that drives the blade so that the saw blade that has cut the workpiece passes through the cut groove and exits the workpiece;
a transition control unit that controls the drive device to transition from the first mode cutting to the second mode cutting while the blade is held within the cut groove,
The workpiece has a second surface where the saw blades that cut the workpiece enter the workpiece in the first cutting mode, and a first surface where the saw blades that entered the workpiece exit the workpiece,
The second cutting control unit controls the drive device so that the saw blades cutting the workpiece transition from a state in which they enter the workpiece from the second surface at the end of cutting in the first mode and exit the workpiece through the cut groove to a state in which they enter the workpiece from the first surface at the end of cutting in the first mode and exit the workpiece through the cut groove. The workpiece has a substantially rectangular cross-sectional shape,
The drive device is
a rotation drive unit that rotates the blade about a rotation axis that passes through a center of the periphery so as to circulate the sawtooth in a first circulation direction along the periphery;
a first displacement drive unit that moves the blade along a first moving direction perpendicular to the rotation axis;
a second displacement drive unit that moves the blade along a second traveling direction that is perpendicular to the rotation axis and intersects with the first traveling direction,
the first cutting control unit moves the blade by the first displacement drive unit in the first mode of cutting;
The sawing device according to claim 3 , wherein the second cutting control section moves the blade by the second displacement drive section in the second mode of cutting.