WO2024004363A1 - Deburring tool and deburring method - Google Patents

Abstract

This deburring tool (1) has a cylindrical shaft part (2). When the distal end side of the shaft part (2) is a first direction (X1) and the proximal end side is a second direction (X2), the shaft part (2) comprises: a guide section (6) having an annular guide surface (6a); and a cutting-edge-forming section (7) having an outer peripheral surface (11) that is continuous in the second direction (X2) of the guide surface (6a). The cutting-edge-forming section (7) is provided with grooves (12) that extend in the second direction (X2) from the guide surface (6a), on the outer peripheral surface (11). At opening edges (20) of the grooves (12) in the cutting-edge-forming section (7), the opening edge (20) portions extending from the guide surface (6a) in the second direction (X2) are cutting edges (25), (26). In a deburring step, the guide surface (6a) and the cutting-edge-forming section (7) are brought into contact with a surface (50a) to be deburred while rotating the deburring tool (1).

Description

Deburring tools and deburring methods

The present invention relates to a rod-shaped deburring tool that removes burrs by bringing its outer peripheral surface into contact with the surface of a workpiece to be deburred.

Such a deburring tool is described in Patent Document 1. The deburring tool disclosed in the document includes an outer circumferential surface surrounding the axis, a front end surface perpendicular to the axis, and a groove having a constant width that crosses the center of the front end surface in a direction perpendicular to the axis. The groove extends parallel to the axis from the front end surface of the deburring tool toward the proximal end. The front end portion of the deburring tool is divided into two blade portions by a groove. The opening edge of the groove includes a leading edge portion with a continuous front end surface and an outer peripheral edge portion with a continuous outer peripheral surface. The outer peripheral edge portion extends in the axial direction from the front end surface. The outer peripheral edge portion is the cutting edge of the deburring tool.

When removing burrs, position the deburring tool so that its axis is parallel to the surface of the workpiece to be deburred. Further, while the deburring tool is being rotated around the axis, the outer peripheral surface of the shaft portion is brought into contact with the surface of the workpiece to be deburred, and the deburring tool is moved along the deburring target surface. As a result, the burrs existing on the edge of the surface to be burred are sheared off by the cutting blade.

Unexamined Japanese Patent Publication No. 2016-2618

The deburring tool of Patent Document 1 has a problem in that the cutting blade bites into the surface to be deburred during the deburring process, easily damaging the surface of the workpiece. This problem will be explained with reference to FIGS. 14 and 15. FIG. 14 is a perspective view of the deburring tool disclosed in Patent Document 1. FIG. 15 is an explanatory diagram of the deburring operation by the deburring tool of Patent Document 1, when viewed from the front end surface side of the deburring tool. FIG. 15(a) shows a state in which the outer circumferential surface of the deburring tool is in contact with the surface to be deburred. FIG. 15(b) shows a state in which the groove of the deburring tool faces the surface to be deburred. FIG. 15(c) shows a state in which the deburring tool has further rotated from the state shown in FIG. 15(b).

As shown in FIG. 14, the deburring tool 100 of the same document includes a shaft portion 101. The shaft portion 101 includes an outer circumferential surface 102 surrounding the axis L0, a front end 103 perpendicular to the axis L0, and a groove 104 having a constant width that crosses the center of the front end 103 in a direction orthogonal to the axis L0. The groove 104 extends from the front end portion 103 toward the proximal end in parallel with the axis L0. The opening edge of the groove 104 includes a leading edge portion 104a where the front end 103 is continuous, and an outer peripheral edge portion 104b where the outer peripheral surface 102 is continuous. The outer peripheral edge portion 104b extends from the front end portion 103 in the direction of the axis L0. The outer peripheral edge portion 104b is the cutting edge 105 of the deburring tool 100. In the shaft portion 101, the inner wall surface of the groove 104 extending inward from the cutting edge 105 is a rake surface of the cutting edge 105. The rake angle θ0 formed between the rake face and the outer circumferential surface 102 of the shaft portion 101 is an acute angle. In other words, the cutting edge 105 of the deburring tool 100 has an acute angle.

As shown in FIG. 15, when removing burrs, the deburring tool 100 is placed in a position where its axis L0 is parallel to the surface 110a of the workpiece 110 to be deburred. In addition, when removing burrs, as shown in FIG. 15(a), with the deburring tool 100 rotated around the axis, the outer circumferential surface 102 of the shaft portion 101 is moved to the burr removal target surface 110a of the workpiece 110. It is moved along the burr removal target surface 110a.

Thereafter, as shown in FIG. 15(b), at a rotation angle position where the groove 104 of the rotating deburring tool 100 faces the deburring target surface 110a, the deburring tool 100 and the deburring target surface 110a face each other. In this direction, the arc-shaped outer circumferential surface 102 no longer exists between the deburring tool 100 and the surface 110a to be deburred.

Here, the deburring tool 100 is always pressed against the surface 110a to be deburred during the machining operation. Therefore, when the deburring tool 100 transitions from the state shown in FIG. 15(a) to the state shown in FIG. 15(b), the outer peripheral surface 102 no longer exists between the deburring tool 100 and the surface 110a to be deburred. By this amount, the shaft portion 101 approaches the burr removal target surface 110a. That is, the axis L0 of the shaft portion 101 approaches the burr removal target surface 110a, and the burr removal target surface 110a is located inside the outer circumferential surface 102 of the shaft portion 101. Therefore, as shown in FIG. 15(c), when the deburring tool 100 further rotates, the cutting edge 105, which is the opening edge of the groove 104 provided on the outer circumferential surface 102, scrapes the surface 110a to be deburred. .

In view of the above problems, an object of the present invention is to provide a deburring tool that can prevent or suppress damage to the surface of the workpiece to be deburred during the deburring operation.

In order to solve the above problems, the deburring tool of the present invention has a cylindrical shaft, and the direction along the axis of the shaft is such that one side in the axial direction is the front and the other side is the rear. In this case, the shaft portion includes a guide portion having an annular guide surface around the axis, and a cutting edge forming portion including a cutting edge extending rearward from the guide surface, and the cutting edge forming portion includes: an outer circumferential surface continuous to the rear of the guide surface; and a groove provided on the outer circumferential surface, the groove extending from the guide surface to the rear, and having the deepest depth at a central portion in the axial direction; At the opening edge of the groove in the cutting edge forming portion, the opening edge portion extends from the guide surface toward the rear, and becomes shallow from the central portion toward the front, and becomes shallow from the central portion toward the rear. , the cutting edge is characterized in that the entirety of the cutting edge forming portion overlaps with the guide portion when viewed from the axial direction.

According to the present invention, the shaft portion includes a guide portion having an annular outer circumferential surface on the front side of the cutting edge forming portion where the cutting edge is provided. Further, the entire cutting edge forming portion overlaps with the guide portion when viewed from the axial direction. That is, the cutting edge forming portion does not have a portion that projects outward from the guide surface. Therefore, when removing burrs by bringing the rotating shaft into contact with the surface of the workpiece to be deburred, if the guide part is in contact with the surface to be deburred, the surface to be deburred will be on the inner side of the guide surface. It is possible to prevent or suppress the situation from occurring. Therefore, it is possible to prevent or suppress the cutting blade provided in the cutting blade forming portion from scraping the surface to be deburred.

Furthermore, in the present invention, since the cutting edge forming portion including the cutting edge includes an outer circumferential surface continuous to the rear of the guide surface, it is easier to prevent the cutting edge from scraping the surface to be deburred. Furthermore, in the present invention, the depth of the groove is the deepest at the central portion in the axial direction, becomes shallower from the central portion toward the tip side, and becomes shallower from the central portion toward the second direction. . Therefore, the burr sheared by the cutting blade can be easily discharged from the groove.

In the present invention, the groove includes a first inner wall surface and a second inner wall surface that face each other in a circumferential direction around the axis, and extends in the circumferential direction to meet an inner circumferential end of the first inner wall surface and the second inner wall surface. a bottom surface that connects an end on the inner peripheral side of the wall surface, and the opening edge portion includes a corner portion where the first inner wall surface and the outer peripheral surface intersect, and a bottom surface that connects the inner peripheral side end of the wall surface, and a corner portion where the first inner wall surface and the outer peripheral surface intersect. It may be a corner that intersects. In this way, the deburring operation can be performed regardless of the direction in which the deburring tool is rotated.

In the present invention, the groove may extend in the axial direction with a constant width, and the first inner wall surface and the second inner wall surface may each extend in a radial direction centered on the axis.

By the way, the teeth of a helical gear are formed by hobbing or skyping. These cutting processes generate larger burrs than general cutting processes. Here, as the burr becomes larger, the strength of the root portion of the burr increases. Therefore, when removing burrs generated on helical gears, a load is applied to the cutting blade of the deburring tool. Therefore, if the cutting edge has an acute angle, chipping is likely to occur on the cutting edge. On the other hand, if the first inner wall surface and the second inner wall surface of the groove, which serve as the rake surfaces of the cutting edges, each extend in the radial direction, each cutting edge becomes a right angle. That is, the angle formed between the outer circumferential surface of the cutting edge forming portion and the first inner wall surface, which is the rake surface of one of the cutting edges, is 90°. Further, the angle formed between the outer circumferential surface of the cutting edge forming portion and the second inner wall surface which is the rake surface of the other cutting edge is 90°. Therefore, even when the deburring tool is used to remove strong burrs such as burrs generated on helical gears, chipping on the cutting edge can be prevented or suppressed.

In the present invention, the cutting edge forming portion may have a constant outer diameter dimension in the axial direction.

In the present invention, the outer diameter of the cutting edge forming portion may become smaller toward the second direction. This prevents or suppresses damage to the surface to be deburred by the rear end of the cutting blade when the rear end of the shaft is inclined in a direction approaching the surface to be deburred during deburring. can.

The shaft portion may include a front end portion provided at an end in the first direction with an annular curved outer circumferential surface that curves inward from the guide surface toward the first direction. By providing such a front end portion, it is possible to prevent or suppress the tip of the shaft portion from damaging the surface to be deburred when the shaft portion is inclined with respect to the surface to be deburred during the deburring process.

In the present invention, the shaft portion may include a cylindrical portion having the same outer diameter as the guide portion in the second direction of the cutting edge forming portion. In this case, if the deburring operation is performed with the guide part and the cylindrical part in contact with the surface to be deburred, it is possible to prevent the proximal end of the shaft part from tilting in the direction toward the deburring target surface during the deburring process. It can be prevented. Therefore, it is possible to prevent or suppress damage to the surface to be deburred by the proximal end portion of the cutting blade.

In the present invention, a rake face of the cutting edge extending inward from the cutting edge extends in the radial direction, and a flank surface of the cutting edge extending in the circumferential direction from the cutting edge when viewed from the axial direction. It may extend inside the guide surface. In this way, a sharp cutting edge can be provided.

Next, in the deburring method of the present invention, the rear end portion of the shaft of the deburring tool is attached to a machine tool via a radial floating holder, and the radial floating holder and the deburring tool are connected to the axis. The guide part and the cutting blade forming part are brought into contact with the surface to be removed of burrs of the workpiece in a state of being rotated in the same direction, and are moved along the surface to be removed of burrs to remove burrs from the surface to be removed. shall be.

By attaching the deburring tool to a machine tool via a radial floating holder and performing deburring operations, you can remove burrs from the burr side when the burrs rising from the surface to be deburred are too hard to shear with the cutting blade. The force acting on the cutting edge forming portion causes the shaft portion to move in a direction orthogonal to the axis. That is, if the burr cannot be sheared, the cutting blade forming portion including the cutting blade moves in a direction away from the surface to be removed. Therefore, during the deburring process, it is possible to prevent or suppress the cutting blade from biting into the burrs and the surface to be deburred and damaging the surface to be deburred. Further, due to the presence of burrs having high hardness, it is possible to prevent or suppress the occurrence of chipping on the cutting edge during the deburring process.

According to the deburring tool and deburring method of the present invention, it is possible to prevent or suppress the cutting blade from damaging the surface of the workpiece to be deburred.

FIG. 2 is a perspective view of the deburring tool of Example 1. 2 is a side view of the deburring tool of Example 1. FIG. 3 is a sectional view taken along line AA in FIG. 2. FIG. 3 is a sectional view taken along line BB in FIG. 2. FIG. It is an explanatory view of a deburring method using a deburring tool. It is a flowchart of a deburring method. It is an explanatory view of the deburring operation which removes the burr of a bevel gear. It is an explanatory view of a deburring tool of a modification. It is an explanatory view of the deburring method using the deburring tool of a modification. FIG. 3 is a perspective view of a deburring tool according to a second embodiment. FIG. 7 is a side view of the deburring tool of Example 2. 12 is a sectional view taken along the line CC in FIG. 11. 12 is a sectional view taken along line DD in FIG. 11. FIG. FIG. 2 is a perspective view of a conventional deburring tool. It is an explanatory view of deburring operation by a conventional deburring tool.

Hereinafter, a deburring tool and a deburring method according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of the deburring tool. In FIG. 1, the deburring tool is viewed from the front. FIG. 2 is a side view of the deburring tool. FIG. 3 is a cross-sectional view taken along line AA in FIG. In FIG. 3, the deburring tool is cut along the axis. FIG. 4 is a sectional view taken along line BB in FIG. In FIG. 4, the cutting edge forming portion of the deburring tool is cut in a direction perpendicular to the axis. As shown in FIG. 1, the deburring tool 1 of this example has a cylindrical shaft portion 2. As shown in FIG. The shaft portion 2 is made of cemented carbide or high speed tool steel (high speed steel). In the following description, the direction along the axis L of the shaft portion 2 is referred to as the axial direction X, the front side of the shaft portion 2 in the axial direction X is the first direction X1, and the side opposite to the first direction X1 in the axial direction side) is defined as the second direction X2. The second direction X2 is the base end side of the shaft portion 2.

As shown in FIGS. 1 to 3, the shaft portion 2 includes, from the end in the first direction X1 toward the second direction X2, a front end portion 5, a guide portion 6, a cutting edge forming portion 7, a columnar portion 8, and a The parts 9 are provided in this order. The front end portion 5 includes a circular front end surface 5a and an annular curved outer peripheral surface 5b that curves in the second direction X2 toward the outer peripheral side from the front end surface 5a.

The guide portion 6 includes an annular guide surface 6a around the axis. The width of the guide surface 6a in the axial direction X is constant in the circumferential direction. The curved outer circumferential surface 5b of the front end portion 5 continues to the end of the guide surface 6a in the first direction X1 without a step. In other words, the front end portion 5 includes an annular curved outer peripheral surface 5b that curves inward from the guide surface 6a of the guide portion 6 toward the first direction X1.

The entire cutting edge forming portion 7 overlaps with the guide portion 6 when viewed from the axial direction X. That is, as shown in FIG. 4, the cutting edge forming portion 7 does not have a portion that protrudes toward the outer circumferential side from the guide surface 6a when viewed from the axial direction X. The cutting edge forming portion 7 includes an outer circumferential surface 11 that is continuous in the second direction X2 of the guide surface 6a. Further, the cutting edge forming portion 7 includes a plurality of grooves 12 extending from the guide portion 6 in the second direction X2 on the outer circumferential surface 11 thereof. The outer peripheral surface 11 is a circular arc surface centered on the axis L. In this example, the cutting edge forming portion 7 includes six grooves 12. Each groove 12 extends in the axial direction X with a constant width.

As shown in FIG. 2, each groove 12 is a rectangle long in the axial direction X when viewed from the radial direction. Each groove 12 includes a first inner wall surface 13 and a second inner wall surface 14 that face each other in the circumferential direction around the axis. Furthermore, each groove 12 includes a rectangular bottom surface 17 that is long in the axial direction X when viewed from the radial direction. The bottom surface 17 extends in the circumferential direction and connects the inner circumferential end of the first inner wall surface 13 and the inner circumferential end of the second inner wall surface 14 .

Here, as shown in FIG. 3, each groove 12 has the deepest depth at the center portion in the axial direction X, becomes shallower from the center portion toward the first direction X1, and becomes shallower from the center portion toward the second direction X2. It gets shallower towards the end. The end of the bottom surface 17 in the first direction X1 is at the same height as the outer circumferential surface 11. That is, the end of the bottom surface 17 in the first direction X1 is at the same height as the guide surface 6a. Further, the end of the bottom surface 17 in the second direction X2 is at the same height as the outer circumferential surface 11. That is, the end of the bottom surface 17 in the second direction X2 is at the same height as the annular outer circumferential surface 8a of the columnar portion 8. The cross-sectional shape of the bottom surface 17 of the groove 12 is an arc whose central portion in the axial direction X is depressed toward the inner circumferential side.

As shown in FIG. 2, the opening edge 20 of each groove 12 in the cutting edge forming portion 7 is rectangular. The opening edge 20 of each groove 12 includes a first opening edge portion 21 and a second opening edge portion 22 that face each other in the circumferential direction. The opening edge 20 also includes a third opening edge portion 23 connecting the end of the first opening edge portion 21 in the first direction X1 and the end of the second opening edge portion 22 in the first direction X1, and a first opening edge portion. 21 in the second direction X2 and a fourth opening edge portion 24 connecting the end of the second opening edge portion 22 in the second direction X2. The first opening edge portion 21 and the second opening edge portion 22 each extend in the second direction X2 from the guide surface 6a.

In the opening edge 20 of each groove 12 in the cutting edge forming portion 7, the first opening edge portion 21 extending from the guide surface 6a in the second direction X2 is the first cutting edge 25. Further, in the opening edge 20 of each groove 12, a second opening edge portion 22 extending from the guide surface 6a in the second direction X2 is a second cutting edge 26. Here, the first opening edge portion 21 is an edge on the outer circumferential side of the first inner wall surface 13 , and the second opening edge portion 22 is an edge on the outer circumferential side of the second inner wall surface 14 . Therefore, the first cutting edge 25 is a corner portion where the first inner wall surface 13 and the outer circumferential surface 11 of the cutting edge forming portion 7 intersect. The second cutting edge 26 is a corner portion where the second inner wall surface 14 and the outer circumferential surface 11 of the cutting edge forming portion 7 intersect. Further, the first inner wall surface 13 that is continuous to the inner peripheral side of the first opening edge portion 21 is the first rake surface of the first cutting edge 25 . The second inner wall surface 14 continuous to the inner peripheral side of the second opening edge portion 22 is a second rake surface of the second cutting edge 26 .

As shown in FIG. 4, the first inner wall surface 13 and the second inner wall surface 14 of each groove 12 each extend in a radial direction centered on the axis L. That is, the rake face (first inner wall surface 13) of the first cutting edge 25 extends in the radial direction. On the other hand, the flank surface of the first cutting edge 25 is the outer circumferential surface 11 of the shaft portion 2 . Therefore, the relief angle of the first cutting edge 25 is 0°. Therefore, the first angle θ1 formed by the outer circumferential surface 11 (flank surface) of the cutting edge forming portion 7 and the rake surface of the first cutting edge 25 is 90°. That is, the first cutting edge 25 is at a right angle. Further, the second inner wall surface 14, which is the rake surface of the second cutting edge 26, extends in the radial direction. On the other hand, the clearance surface of the first cutting edge 25 is the outer peripheral surface 11 of the shaft portion 2, and the clearance angle of the first cutting edge 25 is 0°. Therefore, the second angle θ2 formed by the outer circumferential surface 11 of the cutting edge forming portion 7 and the second inner wall surface 14, which is the rake surface of the second cutting edge 26, is 90°. That is, the second cutting edge 26 is at a right angle.

As shown in FIG. 1, the cylindrical portion 8 includes an annular outer circumferential surface 8a. The outer diameter of the annular outer peripheral surface 8a is the same as the outer diameter of the guide surface 6a. The annular outer peripheral surface 8a has a constant width in the axial direction X in the circumferential direction. Here, the outer diameter dimension of the cutting edge forming part 7 is the same as the outer diameter dimension of the guide part 6 and the outer diameter dimension of the cylindrical part 8. Further, the outer diameter dimension of the cutting edge forming portion 7 is constant in the axial direction X. Therefore, the outer circumferential surface 11 of the cutting edge forming part 7 and the guide surface 6a of the guide part 6 are continuous without any difference in level. Further, the outer circumferential surface 11 of the cutting edge forming portion 7 and the annular outer circumferential surface 8a of the cylindrical portion 8 are continuous without any step.

The shank portion 9 is a portion located further in the second direction X2 than the cylindrical portion 8. The shank portion 9 is a portion that is chucked to a spindle of a machine tool. In this example, the shank portion 9 has a cylindrical shape. Further, the outer diameter of the shank portion 9 is the same as that of the cylindrical portion 8, and there is no boundary between the cylindrical portion 8 and the shank portion 9. Note that the shank portion 9 may be provided with a D cut or the like.

(Deburring method)
FIG. 5 is an explanatory diagram of a deburring method using the deburring tool 1. FIG. 6 is a flowchart of a deburring method using the deburring tool 1. As shown in FIG. In the example shown in FIG. 5, the workpiece 50 is a helical gear. The surface 50a of the workpiece 50 to be deburred is the end face of the tooth of the helical gear, and a portion of the end face of the helical gear adjacent to the inner peripheral side of the tooth. In the example shown in FIG. 5, the burr 55 generated on the edge of the end face of the tooth of the helical gear is removed by the deburring tool 1.

As shown in FIGS. 5 and 6, when deburring the workpiece 50, the deburring tool 1 is attached to the spindle 52a of the machine tool 52 via the radial floating holder 51 (step ST1). After that, while driving the machine tool 52 and rotating the deburring tool 1 in the first rotation direction R1 around the axis, the guide surface 6a and the outer circumferential surface 11 of the cutting edge forming part 7 are removed from the workpiece 50 for deburring. It is brought into contact with the surface 50a and moved along the burr removal target surface 50a (step ST2). Thereby, the deburring tool 1 shears off the burr 55 present on the edge of the surface 50a to be deburred. The cutting edge used when the deburring tool 1 is rotated in the first rotation direction R1 is the first cutting edge 25.

In this example, the annular outer circumferential surface 8a of the cylindrical portion 8 is not brought into contact with the surface 50a to be deburred. Further, during the deburring process, the curved outer circumferential surface 5b of the front end portion 5 does not come into contact with the surface 50a to be deburred. Note that the rotation direction of the deburring tool 1 may be opposite to the first rotation direction R1. In this case, the cutting edge that shears the burr 55 is the second cutting edge 26.

Here, the radial floating holder 51 is a common one. The radial floating holder 51 holds the deburring tool 1 so as to be movable in a direction perpendicular to the axis L thereof. Further, during the deburring process, when the guide surface 6a and the outer circumferential surface 11 of the cutting edge forming part 7 are in contact with the deburring target surface 50a of the workpiece 50, the radial floating holder 51 allows the deburring tool 1 to touch the workpiece 50. The deburring tool 1 is brought into contact with the surface 50a to be deburred by generating an urging force corresponding to the force (reaction force) received from the burr.

(effect)
According to this example, the shaft portion 2 of the deburring tool 1 has a guide having an annular outer circumferential surface 11 on the tip side of the cutting edge forming portion 7 in which the first cutting edge 25 and the second cutting edge 26 are provided. A section 6 is provided. Further, the entire cutting edge forming portion 7 overlaps with the guide portion 6 when viewed from the axial direction X. That is, the cutting edge forming portion 7 does not have a portion that protrudes toward the outer circumferential side from the guide surface 6a. Therefore, when the outer circumferential surface 11 of the rotating shaft portion 2 is brought into contact with the surface 50a to be removed of burrs of the work 50 to remove the burrs, if the guide portion 6 is brought into contact with the surface 50a to be removed of burrs, the burrs can be removed. It is possible to prevent or suppress the target surface 50a from being located on the inner peripheral side than the guide surface 6a. Therefore, it is possible to prevent or suppress the cutting blades 25 and 26 from scraping the burr removal target surface 50a.

That is, in the conventional deburring tool 100 in which the deburring tool 1 is not provided with the guide part 6, as shown in FIG. 15(b), the rotation angle at which the groove 12 of the deburring tool 100 faces the deburring target surface 50a In this position, the shank 101 approaches the burr removal target surface 110a, and the burr removal target surface 110a is located inside the outer circumferential surface 102 of the shank 101. Therefore, as shown in FIG. 15(c), when the deburring tool 100 further rotates, the cutting edge 105, which is the opening edge of the groove 104 provided on the outer circumferential surface 102, scrapes the surface 110a to be deburred. Sometimes. On the other hand, when the deburring tool 1 of this example is used, the occurrence of such a situation can be prevented or suppressed.

Furthermore, in this example, the cutting edge forming portion 7 including the cutting edges 25 and 26 includes an outer circumferential surface 11 continuous to the rear of the guide surface 6a. Therefore, it is easier to prevent the cutting blades 25 and 26 from scraping the surface to be deburred.

Next, the teeth of the helical gear are formed by hobbing or skyping. In these cutting processes, larger burrs 55 are generated compared to general cutting processes. Here, as the burr 55 becomes larger, the strength of the root portion of the burr increases. Therefore, when removing the burr 55 generated on the helical gear, a load is applied to the cutting blades 25 and 26 of the deburring tool 1. Therefore, when the cutting edges 25 and 26 have acute angles, there is a problem that chipping is likely to occur in the cutting edges 25 and 26.

In contrast, in this example, the first inner wall surface 13 and the second inner wall surface 14 of the groove 12, which serve as the rake surfaces of the cutting blades 25 and 26, each extend in the radial direction. Thereby, the first cutting edge 25 and the second cutting edge 26 become at right angles. Therefore, according to the deburring tool 1 of this example, chipping occurs on the cutting edges 25 and 26 during deburring processing, compared to the case where the deburring tool 100 shown in FIG. 14 has the cutting edge 105 at an acute angle. This can be prevented or suppressed.

Furthermore, in this example, the deburring tool 1 is attached to a machine tool via the radial floating holder 51 to perform the deburring operation. Therefore, when the burr 55 existing on the burr removal target surface 50a is so hard that the cutting blades 25 and 26 cannot shear the burr 55, the force acting on the cutting blade forming part 7 from the burr 55 side causes the shaft part 2 to move along the axis. Move in the orthogonal direction perpendicular to L. That is, when the burr 55 cannot be sheared, the cutting blade forming part 7 including the cutting blades 25 and 26 moves in a direction away from the burr removal target surface 50a. Therefore, during the deburring process, it is possible to prevent or suppress the cutting blades 25 and 26 from biting into the burr 55 and the burr removal target surface 50a and damaging the burr removal target surface 50a. Further, due to the presence of the burr 55 having high hardness, it is possible to prevent or suppress the occurrence of chipping on the cutting blades 25 and 26 during the deburring process.

Furthermore, the depth of the groove 12 is the deepest at the central portion in the axial direction X, becomes shallower from the central portion toward the tip end, and becomes shallower from the central portion toward the second direction X2. Therefore, the burr 55 sheared by the cutting blades 25 and 26 can be easily discharged from the groove 12.

Further, the shaft portion 2 includes a front end portion 5 at the end in the first direction X1, which includes an annular curved outer peripheral surface 5b that curves inward from the guide surface 6a toward the first direction X1. Therefore, when the shaft portion 2 is inclined with respect to the surface 50a to be deburred during the deburring process, it is possible to prevent or suppress the tip of the shaft portion 2 from damaging the surface 50a to be deburred.

Furthermore, in this example, the groove 12 includes a first inner wall surface 13 and a second inner wall surface 14 that face each other in the circumferential direction around the axis L. The outer circumferential end of the first inner wall surface 13 is a first cutting edge 25 , and the outer circumferential edge of the second inner wall surface 14 is a second cutting edge 26 . Therefore, deburring can be performed regardless of the direction in which the deburring tool 1 is rotated.

Here, according to the deburring method using the deburring tool 1, even if the deburring target surface 50a of the workpiece 50 is a curved surface, the deburring target surface 50a is suppressed from being damaged, and the deburring target surface 50a is suppressed from being damaged. The burr 55 generated on the edge of 50a can be removed. FIG. 7 is an explanatory diagram of a deburring operation for removing burrs generated on the end surface of the tooth portion of a bevel gear.

As shown in FIG. 7, the bevel gear 60 includes a cylindrical portion 61 and an umbrella-shaped tooth portion 62 provided on one side in the centerline direction along the centerline M of the cylindrical portion 61. The tooth portion 62 protrudes from the cylindrical portion 61 toward the outer circumference. The tooth portion 62 includes, on the side of the cylindrical portion 61, a first annular tapered surface 62a that is continuous with the outer peripheral surface of the cylindrical portion 61. The first tapered surface 62a is inclined toward the cylindrical portion 61 toward the inner circumferential side. Further, the tooth portion 62 includes a second annular tapered surface 62b on the opposite side from the cylindrical portion 61. The second tapered surface 62b is inclined toward the cylindrical portion 61 toward the inner circumferential side.

Here, when forming teeth on the tooth portion 62 by cutting, burrs 65 are generated on the edges of the first tapered surface 62a and the edges of the second tapered surface 62b. When removing the burr 65 generated on the edge of the first tapered surface 62a, as shown by the solid line in FIG. 1. The deburring tool 1 and the bevel gear 60 are moved relative to each other around the center line of the cylindrical portion 61 while making contact with the tapered surface 62a. Moreover, when removing the burr 65 generated on the edge of the second tapered surface 62b, as shown by the broken line in FIG. The deburring tool 1 and the bevel gear 60 are moved relative to each other around the center line of the cylindrical portion 61 while the deburring tool 1 and the bevel gear 60 are brought into contact with the second tapered surface 62b. In this way, even if the burr removal target surface 50a is a tapered surface, the burr 65 generated on the edge of the burr removal target surface 50a can be removed without damaging the burr removal target surface 50a.

(Other deburring methods)
Here, in the deburring tool 1 of this example, the shaft portion 2 includes a cylindrical portion 8 having the same outer diameter as the guide portion 6 in the second direction X2 of the cutting edge forming portion 7. Therefore, when removing burrs formed on the opening edge of a hole formed on the surface 50a to be deburred, the guide surface 6a of the guide portion 6 and the annular outer circumferential surface 8a of the cylindrical portion 8 are removed during the deburring process. The burr 55 can also be removed by moving the deburring tool 1 while in contact with the surface 50a to be deburred. That is, deburring can be performed by bringing the annular outer circumferential surface 8a of the cylindrical portion 8 into contact with the deburring target surface 50a as a second guide surface. In this case, since there are annular surfaces (guiding surface 6a and annular outer peripheral surface 8a) having the same outer diameter as the cutting edge forming portion 7 on both sides of the cutting edge forming portion 7 in the axial direction X, the burr can be removed. During processing, it is possible to prevent the shaft portion 2 from tilting in a direction away from the surface 50a to be deburred. Therefore, the cutting blades 25 and 26 do not bite into the surface 50a to be deburred. Therefore, it is possible to prevent or suppress the deburring tool 1 from damaging the deburring target surface 50a.

(Modified example)
FIG. 8 is a side view of a modified deburring tool. In FIG. 8, the shape of the cutting edge forming portion 7 is shown in an exaggerated manner. FIG. 9 is an explanatory diagram of a deburring method using the deburring tool of FIG. 8. In the deburring tool 1A of this example, the outer diameter dimension of the cutting edge forming portion 7 becomes smaller toward the second direction X2, but other configurations are the same as the deburring tool 1 described above. Therefore, corresponding parts are given the same reference numerals and detailed explanation thereof will be omitted.

In the deburring tool 1A of this example, the outer diameter of the cutting edge forming portion 7 becomes smaller in the second direction X2. That is, the cutting edge forming portion 7 includes a tapered outer circumferential surface 11 whose outer diameter decreases from the guide surface 6a toward the second direction X2. The outer circumferential surface 11 is provided with a plurality of grooves 12 having a constant width and extending in the axial direction X. Among the opening edges 20 of the grooves 12 in the cutting edge forming portion 7, the first opening edge portion 21 and the second opening edge portion 22 extending in the second direction X2 are cutting edges 25 and 26, respectively. Here, the inclination of the outer peripheral surface 11 is very slight. In this example, the end of the cutting edge forming portion 7 in the first direction X1 (boundary with the guide portion 6) has the same diameter as the guide surface 6a, but the end of the cutting edge forming portion 7 in the second direction The diameter is 1 mm shorter than the diameter of the guide surface 6a.

The shape of the cutting edge forming portion 7 in the deburring tool 1A is to cope with the inclination of the deburring tool 1A that occurs during the deburring process. That is, when performing deburring by attaching the shank portion 9 (rear end portion of the shaft portion 2) of the deburring tool 1A to the spindle 52a of the machine tool 52 via the radial floating holder 51, the deburring tool The guide portion 6 and the cutting edge forming portion 7 of 1A are pressed against the surface 50a of the workpiece 50 to be deburred. Therefore, during deburring, the radial floating holder 51 moves the axis L of the deburring tool 1A parallel to the deburring target surface 50a due to the reaction force F applied from the deburring target surface 50a to the guide part 6 and cutting edge forming part 7. There may be cases where it is not possible to maintain this condition. In this case, as shown in FIG. 9, the axis L of the deburring tool 1A is inclined with respect to the rotation axis N of the spindle 52a of the machine tool 52, and the deburring tool 1A is connected to the radial floating holder 51. The side in the second direction X2 approaches the burr removal target surface 50a.

Here, when the deburring tool 1A is tilted, the rear end portions (base end portions) of the cutting blades 25 and 26 that are spaced apart from the guide surface 6a in the second direction X2 bite into the burr removal target surface 50a, and The removal target surface 50a is damaged.

To solve this problem, the outer diameter of the cutting edge forming portion 7 becomes smaller in the second direction X2. Therefore, even when the deburring tool 1A is tilted, it is possible to prevent or suppress the proximal end portions of the cutting blades 25 and 26, which are spaced apart from the guide surface 6a in the second direction X2, from biting into the deburring target surface 50a. Therefore, it is possible to prevent or suppress the deburring tool 1A from damaging the surface 50a to be deburred during the deburring process.

(Other forms)
The number of grooves 12 provided in the cutting edge forming portion 7 is not limited to six. Further, each groove 12 may have a width increasing toward the second direction X2. In this case, the first cutting edge 25 and the second cutting edge 26 are inclined in a direction away from each other toward the second direction X2. Further, each groove 12 may have a width increasing toward the first direction X1. In this case, the first cutting edge 25 and the second cutting edge 26 are inclined in a direction away from each other toward the first direction X1. Further, each groove 12 may be inclined toward one side in the circumferential direction from the guide surface 6a toward the second direction X2.

(Example 2)
FIG. 10 is a perspective view of the deburring tool of Example 2. FIG. 11 is a side view of the deburring tool of Example 2. FIG. 12 is a sectional view taken along line CC in FIG. 11. FIG. 13 is a sectional view taken along the line DD in FIG. 11. In FIG. 10, the deburring tool 1B of this example is viewed from the front side. In FIG. 12, the deburring tool 1B is cut along the axis L1. In FIG. 13, the cutting edge forming portion 7 of the deburring tool 1B is cut in a direction perpendicular to the axis L1. Since the deburring tool 1B of the second embodiment has a configuration corresponding to that of the deburring tool 1 described above, the corresponding configurations are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

As shown in FIG. 10, the deburring tool 1B of this example has a cylindrical shaft portion 2. The shaft portion 2 includes a front end portion 5, a guide portion 6, a cutting edge forming portion 7, a cylindrical portion 8, and a shank portion 9 in this order from the end in the first direction X1 toward the second direction X2. The front end portion 5 includes a circular front end surface 5a and an annular curved outer peripheral surface 5b that curves in the second direction X2 toward the outer peripheral side from the front end surface 5a. The guide portion 6 includes an annular guide surface 6a around the axis L1. The width of the guide surface 6a in the axial direction X is constant in the circumferential direction. The front end portion 5 includes an annular curved outer circumferential surface 5b that curves inward from the guide surface 6a of the guide portion 6 toward the first direction X1.

The cylindrical portion 8 includes an annular outer circumferential surface 8a. The outer diameter of the annular outer peripheral surface 8a is the same as the outer diameter of the guide surface 6a. The annular outer peripheral surface 8a has a constant width in the axial direction X in the circumferential direction. The shank portion 9 is a portion located further in the second direction X2 than the columnar portion 8.

The cutting edge forming portion 7 is a portion of the shaft portion 2 located between the guide portion 6 and the cylindrical portion 8 in the axial direction X. As shown in FIG. 13, the entire cutting edge forming portion 7 overlaps with the guide portion 6 when viewed from the axial direction X. That is, as shown in FIG. 13, the cutting edge forming portion 7 does not have a portion that protrudes further toward the outer circumferential side than the guide surface 6a when viewed from the axial direction X. As shown in FIGS. 10 and 13, the cutting edge forming portion 7 includes four blade portions 30 provided at equal angular intervals around the axis L1. Further, the cutting edge forming portion 7 includes four recesses 31 that are recessed toward the inner circumference between the respective blade portions 30 in the circumferential direction. As shown in FIGS. 10 and 11, each blade portion 30 includes a cutting edge 32 extending from the guide surface 6a in the second direction X2 on one side in the circumferential direction. Therefore, the cutting edge forming portion 7 includes four cutting edges 32 provided at equal angular intervals around the axis L1.

Each cutting edge 32 extends parallel to the axis L1 from the guide surface 6a toward the second direction X2. Here, each cutting edge 32 overlaps with the guide surface 6a when viewed from the axis L1 direction. That is, as shown in FIG. 10, each cutting edge 32 defines a virtual cylinder V that is coaxial with the guide portion 6 and has the same outer diameter dimension and extends from the guide surface 6a in the second direction X2. It extends in the second direction X2 while being in contact with.

As shown in FIGS. 11 and 13, each blade portion 30 includes a rake surface 30a that extends inward in the radial direction from the cutting edge 32. Therefore, the rake angle of the cutting edge 32 is 90°. Further, each blade portion 30 includes a flank surface 30b extending circumferentially from the cutting edge 32. As shown in FIG. 13, when viewed from the direction of the axis L1, the flank 30b extends linearly inside the guide surface 6a. Therefore, the clearance angle of each cutting edge 32 is larger than 0°. Therefore, each cutting edge 32 has an acute angle. In the flank 30b, an end edge 30c on the side opposite to the cutting blade 32 in the circumferential direction has an arcuate shape in which a central portion in the axial direction X is recessed toward the cutting blade 32 side. The guide surface 6a is continuous in the first direction X1 of the end 30d of the end edge 30c in the first direction X1. The annular outer peripheral surface 8a of the columnar portion 8 is continuous in the second direction X2 of the end 30e in the second direction X2 of the end edge 30c.

Here, the edge 30c of the flank 30b on the side opposite to the cutting edge 32 in the circumferential direction is an opening edge portion on one side in the circumferential direction of the opening edge of the recess 31. The opening edge on the other side in the circumferential direction of the opening edge of the recessed part 31 is the cutting edge 32 of the blade part 30 located on the other side in the circumferential direction of the recessed part 31 . Each recess 31 is long in the axial direction X when viewed from the radial direction. As shown in FIG. 12, each recess 31 has the deepest depth at the central portion in the axial direction X, becomes shallower from the central portion toward the first direction X1, and becomes shallower from the central portion toward the second direction X2. Become.

When deburring the workpiece 50 using the deburring tool 1B of this example, the deburring tool 1B is moved through the radial floating holder 51 in the same manner as the deburring direction of the deburring tool 1B shown in FIG. , and attached to the spindle 52a of the machine tool 52 (step ST1). After that, while driving the machine tool 52 and rotating the deburring tool 1B in the second rotation direction R2 around the axis L1, the guide surface 6a and the outer circumferential surface 11 of the cutting edge forming part 7 are deburred from the workpiece 50. It is brought into contact with the target surface 50a and moved along the burr removal target surface 50a (step ST2). Thereby, the deburring tool 1B shears off the burr 55 present on the edge of the surface 50a to be deburred. In this example, the deburring tool 1B is not used while being rotated in the first rotation direction R2.

Note that the flank surface 30b extending in the circumferential direction from the cutting edge 32 may be curved. For example, the flank 30b may be an arc that curves in a direction away from the guide surface 6a as it moves away from the cutting blade 32 inside the guide surface 6a when viewed from the direction of the axis L1.

Also in this example, the shaft portion 2 of the deburring tool 1B includes a guide portion 6 having an annular outer circumferential surface 11 on the tip side of the cutting edge forming portion 7 where the cutting edge 32 is provided. Therefore, when the cutting edge forming part 7 of the rotating shaft part 2 is brought into contact with the burr removal target surface 50a of the workpiece 50 to remove the burr 55, if the guide part 6 is brought into contact with the burr removal target surface 50a, It is possible to prevent or suppress the burr removal target surface 50a from being located on the inner peripheral side of each cutting edge 32. Therefore, it is possible to prevent or suppress the cutting blade 32 from scraping the burr removal target surface 50a.

In addition, also in the deburring tool 1B of this example, the outer diameter dimension of the cutting edge forming part 7 may be made smaller toward the second direction X2. That is, the cutting edge 32 of each blade portion 30 may be slightly inclined toward the inner circumferential side toward the second direction X2. In this case, if each cutting edge 32 is defined as a virtual truncated cone that is coaxial with the guide portion 6 and whose outer diameter decreases from the guide surface 6a toward the second direction Provided so that it is in contact with. In this way, even if the deburring tool 1B is tilted during the deburring process in which the deburring tool 1B is connected to the spindle 52a of the machine tool 52 via the radial floating holder 51, the guide surface It is possible to prevent or suppress the proximal end portion of the cutting blade 32 that is spaced apart from the cutting edge 6a in the second direction X2 from biting into the burr removal target surface 50a. Therefore, it is possible to prevent or suppress the deburring tool 1A from damaging the surface 50a to be deburred during the deburring process.

Claims (9)

It has a cylindrical shaft,
When one side in the axial direction is the front side and the other side is the rear side in the direction along the axis of the shaft part, the shaft part has a guide part having an annular guide surface around the axis, and a guide part having an annular guide surface around the axis, and a cutting edge forming portion including the cutting edge extending rearward;
The cutting edge forming portion includes an outer circumferential surface continuous to the rear of the guide surface, and a groove provided on the outer circumferential surface,
The groove extends from the guide surface toward the rear, and is deepest at a central portion in the axial direction, becomes shallower from the central portion toward the front, and becomes shallower from the central portion toward the rear. ,
In the opening edge of the groove in the cutting edge forming portion, the opening edge portion extending from the guide surface to the rear is a cutting edge,
The deburring tool is characterized in that when viewed from the axial direction, the cutting edge forming portion entirely overlaps with the guide portion. The groove includes a first inner wall surface and a second inner wall surface that face each other in a circumferential direction around the axis, and extends in the circumferential direction between an inner circumferential end of the first inner wall surface and an inner circumferential edge of the second inner wall surface. a bottom surface that connects the side edges;
The burr according to claim 1, wherein the opening edge portion is a corner where the first inner wall surface and the outer circumferential surface intersect, and a corner where the second inner wall surface and the outer circumferential surface intersect. Removal tool. The groove has a constant width and extends in the axial direction parallel to the axial line,
The deburring tool according to claim 2, wherein the first inner wall surface and the second inner wall surface each extend in a radial direction centered on the axis. The deburring tool according to claim 1, wherein the outer diameter of the cutting edge forming portion is constant in the axial direction. The deburring tool according to claim 1, wherein the outer diameter of the cutting edge forming portion decreases toward the rear. The deburring tool according to claim 1, wherein the shaft portion includes a front end portion having an annular curved outer peripheral surface that curves inward from the guide surface toward the front. The deburring tool according to claim 1, wherein the shaft portion includes a cylindrical portion having the same outer diameter as the guide portion at the rear of the cutting edge forming portion. A rake face of the cutting edge extending inward from the cutting edge extends in the radial direction,
2. The deburring tool according to claim 1, wherein a flank surface of the cutting edge that extends in the circumferential direction from the cutting edge extends inside the guide surface when viewed from the axial direction. Attaching the rear end portion of the shaft portion in the deburring tool according to claim 1 to a machine tool via a radial floating holder,
With the radial floating holder and the deburring tool rotated about the axis, the guide portion and the cutting edge forming portion are brought into contact with a surface to be deburred of the workpiece and moved along the surface to be deburred. A deburring method characterized by removing burrs from the surface to be deburred.

Images