Circular saw distortion specification method

Abstract

To provide a circular saw distortion specification method that can specify a distortion part of a circular saw when reusing the circular saw and so on.SOLUTION: This method, which specifies distortion of a circular saw having a base plate and a plurality of blades formed on an outer peripheral edge of the base plate, has: a first acquisition process in which a laser irradiation part is moved relatively to a top face 2a of a base plate 2 of a circular saw 1 to acquire a surface shape of the base plate 2 on a plurality of scan lines x1 to x5 along an X-axis direction that are parallel to each other; a second acquisition process in which a surface shape of the base plate 2 is acquired on a plurality of scan lines y1 to y5 along a Y-axis direction crossing the X-axis direction that are parallel to each other; and a specification process in which a distortion part is specified by using the surface shape on the plurality of scan lines x1 to x5 in the X-axis direction, and the surface shape on the plurality of scan lines y1 to y5 in the Y-axis direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a method for identifying distortion of a circular saw such as a tipped saw or a metal saw. [Background technology]

[0002] A cutting device having a circular saw such as a tipped saw or a metal saw is used to cut workpieces such as steel and wood. A circular saw has a substantially disk-shaped base plate and a number of blades formed on the outer periphery of the base plate. In recent years, with the demand for high-quality processed products, high-precision specifications are also required for cutting processing.

[0003] For example, a technique for managing the machining thickness of a circular saw is proposed in Patent Document 1. Patent Document 1 describes that the machining thickness of a circular saw can be measured quickly and accurately by placing the circular saw so that the tip of the blade is located in the laser irradiation area between the laser irradiation unit and the light receiving unit, and measuring the machining thickness of the circular saw by rotating the circular saw while irradiating it with a laser. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-53771 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, in addition to improving the quality of processed products, there has been an increasing demand for cost reduction by sharpening (reusing) circular saws. With use, circular saws can lose their sharpness and the approximately circular plate-shaped base plate can become distorted. When the base plate becomes distorted, the blade vibration at the tip of the saw increases when the saw is rotated, which ultimately affects the processing thickness of the circular saw. Therefore, when reusing a circular saw, it is necessary to correct the distortion of the circular saw.

[0006] Conventionally, the process of straightening a circular saw has been carried out in the following manner. 1. Check the entire surface with a ruler to find any protruding parts or areas that need to be hammered. Specifically, the worker places the ruler horizontally against the base of the circular saw several times to identify any distortions. 2. Decide the strength and number of hits. 3. Place the circular saw on the measuring machine and repeat steps 1 and 2 until the appropriate reading is obtained. Here, if you are an experienced worker, you can reduce the number of times you perform steps 1 and 2 above. However, step 1 above (identifying the location of the distortion) is particularly difficult, and it takes a long time to master it. In addition, it depends heavily on the worker's skill, and individual differences in the results are likely to occur. As a result, there may be variation in the correction of distortion, which may affect the processing quality.

[0007] The present invention has been made in consideration of the above circumstances, and has an object to provide a method for characterizing distortion in a circular saw that can accurately identify the location of distortion in the circular saw when reusing the circular saw, etc. [Means for solving the problem]

[0008] The method for identifying distortion in a circular saw of the present invention is a method for identifying the location of distortion in a circular saw having a substrate and a plurality of blades formed on the outer edge of the substrate, the method being characterized by comprising a first acquisition step of moving a laser irradiation unit relative to a flat surface on one side of the substrate of the circular saw to acquire a surface shape of the substrate on a plurality of parallel scanning lines along a first direction, a second acquisition step of acquiring the surface shape of the substrate on a plurality of parallel scanning lines along a second direction that intersects the first direction, and an identification step of identifying the location of distortion using the surface shape at the plurality of scanning lines in the first direction and the surface shape at the plurality of scanning lines in the second direction.

[0009] In the first obtaining step and the second obtaining step, the laser irradiation unit is moved horizontally while being directed toward a flat surface on one side of the board of the circular saw placed horizontally.

[0010] The first direction and the second direction are perpendicular to each other.

[0011] The method is characterized by further comprising a third acquisition step of acquiring the surface shape of the substrate on a scanning line that passes through an intersection of a plurality of scanning lines in the first direction and a plurality of scanning lines in the second direction and that is along a third direction different from the first direction and the second direction.

[0012] In each of the plurality of scanning lines in the first direction and the plurality of scanning lines in the second direction, the intervals between adjacent scanning lines are not equal, and the interval between any pair of scanning lines closer to the inner periphery of the substrate is smaller than the interval between any pair of scanning lines located further outward. Effect of the Invention

[0013] The method for identifying distortion of a circular saw of the present invention includes a first acquisition step of acquiring the surface shape of the substrate on multiple parallel scanning lines along a first direction by moving a laser irradiation unit relative to a plane on one side of the substrate of the circular saw, a second acquisition step of acquiring the surface shape of the substrate on multiple parallel scanning lines along a second direction intersecting the first direction, and an identification step of identifying the location of distortion using the surface shape on the multiple scanning lines in the first direction and the surface shape on the multiple scanning lines in the second direction, so that the method is less dependent on the skill of an individual than, for example, a method using a ruler by an operator, and the location of distortion of the circular saw can be identified with high accuracy even without skilled skills. Furthermore, it also leads to improved workability in the entire process of correcting distortion of a circular saw.

[0014] The above method further includes a third acquisition step of acquiring the surface shape of the substrate on a scanning line that passes through the intersection of multiple scanning lines in the first direction and multiple scanning lines in the second direction and that is along a third direction different from the first and second directions. This makes it possible to grasp, for example, the locations and shapes of protrusions and depressions in more detail, and makes it easier to identify the locations of distortion with higher accuracy.

[0015] Distortion of the substrate is more likely to occur on the inner circumference side (the circle center side), and distortion occurring on the inner circumference side tends to have a greater effect on blade vibration. From this perspective, for example, in each of the multiple scanning lines in the first direction and the multiple scanning lines in the second direction, the intervals between adjacent scanning lines are not equal, and the interval between any pair of scanning lines closer to the inner circumference of the substrate is smaller than the interval between any pair of scanning lines located further outward, so that it is possible to efficiently identify the location of distortion that will have a greater effect on processing quality. [Brief description of the drawings]

[0016] [Figure 1] 1 is a plan view of a circular saw which is the subject of the method of the present invention. [Diagram 2] 4 is a flow chart showing a method for identifying distortion in a circular saw according to the present invention. [Diagram 3] 1 is a schematic diagram showing the configuration of a laser device used in the present invention. [Figure 4] 10A to 10C are diagrams illustrating an example of a method for acquiring a surface shape in a first acquisition step and a second acquisition step. [Diagram 5] FIG. 13 is a diagram for explaining an outline of a specifying process. [Figure 6] 10A to 10C are diagrams illustrating another example of a method for acquiring a surface shape in the first acquiring step and the second acquiring step. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] An example of a circular saw that is the subject of the method of the present invention will be described with reference to Fig. 1. Fig. 1(a) shows a plan view of the entire circular saw, and Fig. 1(b) shows an enlarged view of the periphery of the blade of the circular saw. As shown in Fig. 1(a), the circular saw 1 has a substantially disk-shaped base plate 2 and a plurality of blades 4 formed on the outer periphery of the base plate 2. A mounting hole 3 is formed in the center of the circular saw 1 (base plate 2), and a circular saw shaft (not shown) of a cutting device is inserted into this mounting hole 3. The outer diameter D of the circular saw 1 is not particularly limited, and is, for example, 100 mm to 800 mm, and preferably 100 mm to 400 mm.

[0018] In the circular saw 1, a plurality of blades 4 are provided at a predetermined pitch in the circumferential direction. The circular saw 1 in Fig. 1 is a tipped saw that employs hard tips for the blades 4. Hard tips have excellent wear resistance, and for example, cermet or cemented carbide made by sintering tungsten carbide and cobalt are used. Note that the measurement subject of the present invention is not limited to tipped saws, and may be a metal saw.

[0019] 1(b), each blade 4 has a rake face 4a, which is the surface from which chips flow during cutting, and a clearance face 4b that is approximately perpendicular to the rake face 4a. Each blade 4 is fixed to a blade chamber on the outer periphery of the base plate 2 by silver solder or the like.

[0020] Next, the specifying method of the present invention will be described with reference to Fig. 2. As shown in Fig. 2, the specifying method of the present invention includes (1) a first obtaining step, (2) a second obtaining step, and (3) a specifying step. Then, the distortion specified in these steps is corrected in (4) a hammering step, thereby correcting the distortion of the circular saw.

[0021] The circular saw to which the identification method of the present invention is applied is, for example, a used circular saw. In a used circular saw, the surface of the substrate may become distorted in a wavy manner due to loads from years of use or heat generated during cutting. For example, a partial rise occurs on one side of the plane, and a corresponding depression occurs on the other side of the plane. If the circular saw is rotated while fixing an area including the part where such distortion has occurred, the blade tip is likely to vibrate significantly due to the influence of the distortion. Therefore, when reusing a circular saw, it is necessary to correct the distortion in order to prevent such an event, and it is important to identify the part of the distortion prior to that.

[0022] Steps (1) to (4) shown in FIG. 2 will be described below with reference to the drawing.

[0023] (1) First acquisition process This process involves moving a laser irradiation unit that irradiates a laser relative to a flat surface on one side of the circular saw's substrate to obtain the surface shape of the flat surface. Figure 3 shows a schematic diagram of a laser device equipped with a laser irradiation unit. The laser device 11 has a laser irradiation unit 12 that irradiates a laser as a scanning wave, and a movement mechanism 13 that moves the laser irradiation unit 12. The movement mechanism 13 has, for example, a plurality of rails and a drive unit.

[0024] In Fig. 3, the circular saw 1 is placed on a mounting table 14 so as to be horizontal. The laser irradiation unit 12 is arranged so as to irradiate a laser onto the upper surface 2a (flat surface on one side) of the substrate 2 of the horizontally placed circular saw 1, and in Fig. 3, the laser irradiation unit 12 can be moved horizontally while facing downward by a moving mechanism 13. Note that the step of acquiring the surface shape is performed without rotating the circular saw 1. In this case, the circular saw 1 may be fixed so as not to rotate.

[0025] The laser device 11 measures the surface shape of the upper surface 2a based on a laser emitted from the laser irradiation unit 12 and reflected by the upper surface 2a. The principle of acquiring the surface shape using a laser can be a known principle such as a confocal method or an optical interference method. An existing surface shape measuring device can be used for the device configuration related to the measurement including the laser irradiation unit 12. In this case, the laser device 11 as shown in FIG. 3 is configured by configuring an existing surface shape measuring device to be movable in the horizontal direction.

[0026] In the first acquisition step, the surface shape of the substrate 2 is acquired on a plurality of parallel scanning lines along the first direction. That is, the laser irradiation unit 12 is moved along the plurality of scanning lines to acquire the corresponding surface shape. An example of this acquisition method will be described with reference to FIG. 4.

[0027] Fig. 4 is a plan view of the circular saw, as seen from one side. In Fig. 4 (as well as Figs. 5 and 6), the X-axis direction corresponds to the first direction, and the Y-axis direction corresponds to the second direction.

[0028] In the example of FIG. 4, the surface shape of the upper surface 2a of the substrate 2 is acquired on five scanning lines x1 to x5 along the X-axis direction. In acquiring the surface shape, the laser irradiation unit is moved along x1 to acquire the surface shape on that scanning line, and then the laser irradiation unit is moved along x2 to acquire the surface shape on that scanning line. In this manner, the surface shape is acquired sequentially along each scanning line. In FIG. 4, the five scanning lines x1 to x5 are parallel to each other, and the four intervals between adjacent scanning lines are equal. Among the five scanning lines x1 to x5, x3 is set to pass through the center point O of the circle.

[0029] (2)Second acquisition process In this step, the surface shape of the substrate is acquired along a second direction intersecting with the first direction. In this step, the same device (laser device, etc.) as in the first acquisition step is used. The acquisition method in this step will also be described with reference to FIG. 4.

[0030] In the example of FIG. 4, the surface shape of the upper surface 2a of the substrate 2 is acquired on five scanning lines y1 to y5 along the Y-axis direction. In acquiring the surface shape, the laser irradiation unit is moved along y1 to acquire the surface shape on that scanning line, and then the laser irradiation unit is moved along y2 to acquire the surface shape on that scanning line. In this manner, the surface shape is acquired sequentially along each scanning line. In FIG. 4, the five scanning lines y1 to y5 are parallel to each other, and the four intervals between adjacent scanning lines are equal. Among the five scanning lines y1 to y5, y3 is set to pass through the center point O of the circle.

[0031] The above-mentioned first and second obtaining steps make it possible to grasp an overall outline of the surface shape of the plane on one side of the substrate 2. Note that, although the first direction and the second direction are in a perpendicular relationship (90° relationship) in Fig. 4, this is not limiting and it is sufficient that they intersect.

[0032] Furthermore, the number of scanning lines along the first direction and the number of scanning lines along the second direction are not limited to 5, and can be appropriately set within a range of, for example, 3 to 15. Since it is easy to set scanning lines passing through the circle center point O symmetrically, it is preferable to set the number of scanning lines to an odd number. Furthermore, the number of scanning lines between the first direction and the second direction may be the same or different.

[0033] (3)Specific process This step is a step of identifying the location of the distortion by using the surface shape in a plurality of scanning lines in the first direction and the surface shape in a plurality of scanning lines in the second direction. An example of this identification will be described with reference to FIG.

[0034] FIG. 5 shows the image diagrams of the surface shape on the scanning line x4 and the surface shape on the scanning line y2, and their correspondence with the circular saw. In each image diagram, L1 represents the displacement of the upper surface 2a with respect to the reference line L0. Note that the surface shapes are also acquired for the other scanning lines (see FIG. 4), but these are omitted in FIG. 5 for the sake of explanation. Also, in each surface shape in FIG. 5, the + (plus) side is shown to be rising upward.

[0035] 5, for example, by using the surface shapes of the scanning lines x4 and y2, it can be seen that a rise occurs at the intersection P (periphery including the intersection P) of the scanning lines x4 and y2 on the upper surface 2a of the substrate 2. This makes it possible to identify the location of the distortion as the intersection P. Note that the location of the distortion does not need to be pinpointed, but only needs to be identified as a certain area.

[0036] In this way, by combining multiple rows of surface shapes acquired in different directions, it is possible to identify the location of distortion and even the degree of that distortion (for example, the degree of bulge). Note that although the identification of bulge locations has been described in Figure 5, it is also possible to identify dent locations in the same way.

[0037] (4) Beating process This process is a process in which the parts with distortion identified in the above process are corrected by hammering. For example, in the case of Figure 5, by hammering the area around intersection point P, it is possible to make it flat and correct the distortion. The specific method of the hammering process can be any method that is usually used, such as manual hammering or mechanical hammering. In the hammering process, the strength and number of hits with the hammer are decided, but it takes less time to learn this compared to the process in 1 above.

[0038] Although the specification method of the present invention has been explained using Figs. 2 to 5 above, the specification method of the present invention is not limited to the above-mentioned method.

[0039] 3, the laser irradiation unit 12 is moved relative to the circular saw 1 in the first and second acquisition steps, but conversely, the laser irradiation unit may be fixed and the circular saw may be moved along the X-axis and Y-axis directions. Considering the construction of the movement mechanism and vibrations during movement, it is preferable to move the laser irradiation unit, which is easier to fix to the frame.

[0040] In addition, in Fig. 4, the intervals between adjacent scanning lines in each of the multiple scanning lines in the X-axis direction and the multiple scanning lines in the Y-axis direction are equal, but this is not limited thereto, and at least one interval may be different from the other intervals. An example of an acquisition method in this case is shown in Fig. 6.

[0041] 6, unlike FIG. 4, the intervals between the scanning lines are different. Specifically, among the multiple scanning lines x1 to x5 in the X-axis direction, the intervals between adjacent scanning lines are not equal, and the interval C ii However, there is a gap C located on the outer periphery. i It is smaller than (C ii <C i In addition, in the plurality of scanning lines y1 to y5 in the Y-axis direction, the intervals between adjacent scanning lines are not equal, and the interval C iv However, there is a gap C located on the outer periphery. iii It is smaller than (Civ <C iii ) In this case, "closer to the inner circumference" refers to the inner circumference (closer to the center of the circle) when viewed relatively among the intervals between multiple scanning lines along one direction. Note that the intervals may become smaller continuously or stepwise from the outer circumference side to the inner circumference side.

[0042] For example, as shown in Figure 6, by setting the spacing of the scan lines so that they are denser on the inner circumference and sparser on the outer circumference, it is possible to efficiently identify distortions that are affected by blade vibration while keeping the number of scans to a minimum.

[0043] In order to more accurately identify the location of the distortion, the surface shape may be acquired on a scanning line along a direction different from the X-axis direction and the Y-axis direction, in addition to the X-axis direction and the Y-axis direction. This acquisition step may be called a third acquisition step. In this case, the scanning line preferably passes through an intersection point between a plurality of scanning lines along the X-axis direction and a plurality of scanning lines along the Y-axis direction. For example, as shown in FIG. 5, the surface shape of the substrate 2 can be acquired on a scanning line z that passes through the intersection point P and is along a direction different from the X-axis direction and the Y-axis direction. In addition, the third acquisition step may acquire the surface shape only on one scanning line, taking into account the results of the first acquisition step and the second acquisition step.

[0044] Furthermore, the surface shape of each scanning line obtained by the method of the present invention can be managed and utilized as distortion data for the circular saw. For example, utilizing the distortion data can lead to improved customer trust. From the user's (customer's) perspective, the appearance of the circular saw remains almost unchanged before and after the correction, so correction of circular saw distortion is often a process based on trust. In contrast, by providing the customer with the distortion data for the circular saw obtained by the method of the present invention, the credibility of the processing can be increased, and processing costs can be more easily charged. [Industrial Applicability]

[0045] The identification method of the present invention can accurately identify the location of distortion in a circular saw when reusing the circular saw, and therefore can be widely used in the field of circular saws, greatly contributing to resource conservation, and further contributing to improving customer trust. [Explanation of symbols]

[0046] 1 Circular saw 2. Board 3 Mounting holes 4 blades 11 Laser device 12 Irradiation unit 13 Moving mechanism 14 Placement table O Circle center point P intersection Scan lines x1~x5, y1~y5

Claims

1. A method for identifying a location of distortion in a circular saw having a base plate and a plurality of blades formed on an outer periphery of the base plate, comprising: The method for identifying distortion in a circular saw includes a first acquisition step of acquiring the surface shape of the substrate along a plurality of parallel scanning lines along a first direction by moving a laser irradiation unit relative to a plane on one side of the substrate of the circular saw, a second acquisition step of acquiring the surface shape of the substrate along a plurality of parallel scanning lines along a second direction that intersects the first direction, and an identification step of identifying the location of distortion using the surface shape along the plurality of scanning lines in the first direction and the surface shape along the plurality of scanning lines in the second direction.

2. The method for identifying distortion in a circular saw according to claim 1, characterized in that, in the first acquisition process and the second acquisition process, the laser irradiation unit is moved horizontally while being directed toward a plane on one side of the substrate of the circular saw which is placed horizontally.

3. 3. The method for identifying a distortion of a circular saw according to claim 1, wherein the first direction and the second direction are perpendicular to each other.

4. The method for identifying distortion in a circular saw as described in claim 1 or claim 2, characterized in that the method further includes a third acquisition step of acquiring the surface shape of the substrate on a scanning line that passes through an intersection of a plurality of scanning lines in the first direction and a plurality of scanning lines in the second direction and that is along a third direction different from the first direction and the second direction.

5. 3. A method for identifying distortion in a circular saw as described in claim 1 or claim 2, characterized in that in each of the multiple scanning lines in the first direction and the multiple scanning lines in the second direction, the spacing between adjacent scanning lines is not equal, and the spacing between any pair of scanning lines closer to the inner circumference of the substrate is smaller than the spacing between any pair of scanning lines closer to the outer circumference.

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