Support jig and support method for cutting tool

Abstract

Provided are support jig and a support method for a cutting tool that support a cutting tool for expanding the diameter of a hole penetrating from a first surface to a second surface of a cylindrical member. The cutting tool comprises a cutting part and a pilot. The cutting part is inserted into the hole from the first surface-side to cut the inner surface of the hole. The pilot is provided on a rotary shaft of the cutting part at the tip of the cutting part, with the insertion direction of the cutting part into the hole serving as a reference. The support jig comprises a first base, a guide, and a second base. The first base contacts the first surface such that a straight line perpendicular to the first surface coincides with the rotary shaft of the cutting part at the position of the hole. The guide is disposed on the second surface-side and is provided with an insertion hole into which the pilot is inserted. The second base supports the guide in a state of being swingable about the center axis of the insertion hole, and causes the guide to contact the opening of the hole part.

Description

Cutting tool support jig and support method

[0001] The present disclosure relates to a support jig and a support method for a cutting tool.

[0002] Patent Document 1 discloses an end mill (cutting tool) that leaves no cutting marks on the machined surface when machining materials that would otherwise leave radial cutting marks. The tip of the end mill is formed with a guide portion that fits into a guide hole formed in the workpiece, and when the end mill cuts the countersunk surface of the workpiece, the guide portion fits into the guide hole.

[0003] JP 2010-12532 A

[0004] When the technology described in Patent Document 1 is used to expand the diameter of a hole that penetrates a cylindrical member in the radial direction, in order to increase the precision of the expansion, it is necessary to hold the cylindrical member while maintaining its circularity and to position the rotation axis of the cutting part of the cutting tool toward the central axis of the cylindrical member. Therefore, there is a problem that the cost and labor required to expand the diameter of the hole with precision is likely to increase.

[0005] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a cutting tool support jig and a support method that can reduce costs and labor when accurately expanding the diameter of a hole that penetrates a cylindrical member in the radial direction.

[0006] A support jig for a cutting tool according to the present disclosure supports a cutting tool that expands the diameter of a hole that penetrates from a first surface to a second surface of a cylindrical member. The cutting tool includes a cutting portion and a pilot. The cutting portion is inserted into the hole from the first surface side and cuts the inner surface of the hole. The pilot is provided on the rotation axis of the cutting portion, at the tip of the cutting portion, with the insertion direction of the cutting portion into the hole as a reference. The support jig includes a first base, a guide, and a second base. The first base abuts against the first surface and aligns the rotation axis of the cutting portion with a line perpendicular to the first surface at the position of the hole. The guide has an insertion hole into which the pilot is inserted and is arranged on the second surface side. The second base supports the guide while allowing the central axis of the insertion hole to swing, and abuts the guide against the opening of the hole.

[0007] The first base may contact the first surface at at least a first contact point, a second contact point, and a third contact point, which are different from each other. The first contact point and the second contact point may have equal distances to a line when projected onto a plane perpendicular to the central axis of the cylindrical member. The position of the third contact point may be different from the positions of the first contact point and the second contact point along the central axis of the cylindrical member.

[0008] The second base may be configured to position the intersection of the straight line and the central axis of the insertion hole relative to the hole portion.

[0009] The guide may be formed by a spherical bearing, the central axis of the insertion hole passing through the center of the spherical surface of the spherical bearing, and the spherical surface may abut against the opening.

[0010] The inner diameter of the insertion hole may be smaller than the inner diameter of the hole portion.

[0011] The tool may further include a moving section provided on the first base for moving the cutting section so that the cutting section cuts a range of the inner surface from the first surface to a predetermined depth.

[0012] The predetermined depth may be shorter than the length of the hole from the first surface to the second surface.

[0013] The material of the first surface side of the cylindrical member may be different from the material of the second surface side.

[0014] The material on the second surface side of the cylindrical member may be a composite material.

[0015] The material on the first surface side of the cylindrical member may be aluminum or an aluminum alloy.

[0016] The outer peripheral surface of the cylindrical member may be the first surface, and the inner peripheral surface of the cylindrical member may be the second surface.

[0017] The method of supporting a cutting tool according to the present disclosure includes placing a cylindrical member between a first base and a second base, abutting the first base against a first surface, abutting the guide against a second surface, and inserting the cutting part into the hole with the pilot inserted into the insertion hole.

[0018] According to the present disclosure, it is possible to provide a support jig and a support method for a cutting tool that can reduce costs and labor when accurately expanding the diameter of a hole that penetrates a cylindrical member in the radial direction.

[0019] 1A and 1B are a side view and a cross-sectional view of a support jig for a cutting tool according to an embodiment of the present disclosure, respectively; and a flowchart of a support method for a cutting tool according to an embodiment of the present disclosure.

[0020] Hereinafter, several exemplary embodiments will be described with reference to the drawings. Note that common parts in the drawings are given the same reference numerals, and duplicated explanations will be omitted.

[0021] [Configuration of Support Jig] Fig. 1 is a side view of a support jig for a cutting tool according to an embodiment of the present disclosure. Fig. 2 is a cross-sectional view of the support jig for a cutting tool according to an embodiment of the present disclosure. Fig. 1 shows a side view of the cutting tool DR and the support jig as viewed from a horizontal direction. Fig. 2 shows a cross section along a plane perpendicular to the central axis of a cylindrical member FC in a state in which the support jig is installed relative to the cylindrical member FC.

[0022] The cutting tool DR expands the diameter of the hole HL that penetrates from the first surface to the second surface of the cylindrical member FC. For example, the "first surface" is the outer peripheral surface of the cylindrical member FC, and the "second surface" is the inner peripheral surface of the cylindrical member FC. Conversely, the "first surface" may be the inner peripheral surface of the cylindrical member FC, and the "second surface" may be the outer peripheral surface of the cylindrical member FC. The first surface of the cylindrical member FC is one of the outer peripheral surface and the inner peripheral surface, and the second surface is the other of the outer peripheral surface and the inner peripheral surface.

[0023] Here, the material of the first surface side and the material of the second surface side of the cylindrical member FC to be machined by the cutting tool DR may be different. For example, the cylindrical member FC may be composed of an outer peripheral surface material FC1 and an inner peripheral surface material FC2.

[0024] For example, the material on the second surface side of the cylindrical member FC may be a composite material, and the material on the first surface side of the cylindrical member FC may be aluminum or an aluminum alloy. The configuration of the cylindrical member FC is not limited to the examples given here.

[0025] The following describes a problem that occurs when attempting to enlarge a hole HL that penetrates a cylindrical member FC in the radial direction (a direction perpendicular to the first and second surfaces) using a cutting tool DR without using the support jig according to an embodiment of the present disclosure. For example, when attempting to precisely enlarge the hole HL using the cutting tool DR, it is necessary to hold the cylindrical member FC while maintaining the circularity of the cylindrical member FC. More specifically, it is necessary to load the cylindrical member FC on a machining center or the like and check the reference surface using a probe or the like.

[0026] Then, after confirming that the hole HL is oriented toward the central axis of the cylindrical member FC, it is necessary to perform machining using the cutting tool DR. If the size of the cylindrical member FC is larger than the cutting tool DR, it becomes necessary to prepare a machining center that matches the size of the cylindrical member FC. As a result, it becomes costly and laborious to hold the cylindrical member FC while maintaining its roundness.

[0027] Furthermore, since there is no mark for identifying the central axis of the cylindrical member FC, it is difficult to make the rotation axis of the cutting portion CT of the cutting tool DR perpendicular to the central axis of the cylindrical member FC. Although a method of determining the perpendicular direction using the hole HL is conceivable, if the inner surface of the hole HL has unevenness due to corrosion or the like, the problem of not being able to accurately determine the direction arises.

[0028] The support jig according to the embodiment of the present disclosure solves the above-mentioned problems. For example, it can eliminate the need for a machining center to hold the cylindrical member FC while maintaining the circularity of the cylindrical member FC. Furthermore, it can reduce the cost and labor required to accurately expand the diameter of the hole HL that penetrates the cylindrical member FC in the radial direction.

[0029] The cutting tool DR includes a cutting part CT and a pilot PL. The cutting part CT is inserted into the hole HL from the first surface side and cuts the inner surface of the hole HL. For example, the cutting part CT receives a driving force from a motor included in the cutting tool DR and rotates around a predetermined rotation axis. Then, a blade provided on the outer peripheral surface of the cutting part CT cuts the inner surface of the hole HL.

[0030] Furthermore, the pilot PL is provided on the rotation axis of the cutting part CT at the tip of the cutting part CT, with the insertion direction of the cutting part CT into the hole HL as the reference. The pilot PL is configured in a cylindrical shape, and the outer diameter of the pilot PL may be smaller than the inner diameter of the hole HL. This allows the cutting part CT provided with the pilot PL to be inserted into the hole HL. In consideration of cases where the inner surface of the hole HL has irregularities due to corrosion or the like, the outer diameter of the pilot PL may be set to a size obtained by subtracting a length approximately equal to the size of the irregularities from the inner diameter of the hole HL.

[0031] The support jig includes a first base BS1, a guide GD, and a second base BS2. The cutting tool DR is supported by the first base BS1. When the support jig is installed on the cylindrical member FC, the first base BS1 is placed on the first surface side of the cylindrical member FC, and the second base BS2 and the guide GD are placed on the second surface side of the cylindrical member FC. The cylindrical member FC is then sandwiched between the first base BS1 and the second base BS2.

[0032] The support jig may be configured to move the cutting tool DR in both directions AR1 and AR2. Here, the direction AR1 is a direction along a line CL that is perpendicular to the first surface at the position of the hole HL. The direction AR2 is a direction perpendicular to the direction AR1. The direction AR2 may also be the direction of gravity.

[0033] For example, the support jig may include a moving unit MH provided on the first base BS1. The moving unit MH may be configured to move the cutting tool DR along a straight line CL perpendicular to the first surface at the position of the hole HL. The moving unit MH may be a manual linear motion unit.

[0034] The moving unit MH may move the cutting unit CT so that the cutting unit CT cuts the inner surface of the hole HL in a range from the first surface to a predetermined depth. The predetermined depth may be shorter than the thickness of the cylindrical member FC, i.e., the length of the hole HL from the first surface to the second surface.

[0035] Additionally, the support jig may include a balancer ME that suspends the first base BS1. The balancer ME may be configured to be able to move the cutting tool DR in the direction AR2. The balancer ME may be an electric balancer. By suspending the first base BS1 that holds the cutting tool DR using the balancer ME, the user of the cutting tool DR does not need to support the weight of the cutting tool DR. As a result, the efficiency of work using the cutting tool DR is improved.

[0036] The first base BS1 abuts against the first surface and aligns a straight line CL perpendicular to the first surface with the rotation axis of the cutting part CT at the position of the hole HL.

[0037] For example, the first base BS1 may contact at least a first contact point, a second contact point, and a third contact point that are different from each other on the first surface. In Figures 1 and 2, the description will be given assuming that the contact portions PD1, PD2, and PD3 of the first base BS1 contact the first surface at the first contact point, the second contact point, and the third contact point, respectively.

[0038] The distances to the line CL of the first and second contact points when projected onto a plane perpendicular to the central axis of the cylindrical member FC may be equal. For example, as shown in Fig. 2, the distance D1 between the contact portion PD1 and the line CL and the distance D2 between the contact portion PD2 and the line CL may be set equal. This ensures that the first base BS1 is perpendicular to the line CL, which is perpendicular to the first surface at the position of the hole HL, within the plane perpendicular to the central axis of the cylindrical member FC.

[0039] Furthermore, the position of the third contact point may be different from the positions of the first contact point and the second contact point along the central axis of the cylindrical member FC. For example, as shown in Fig. 1, the position of the abutment portion PD3 may be different from the positions of the abutment portions PD1 and PD2 along the central axis of the cylindrical member FC. This allows the tilt of the first base BS1 to be fixed with respect to the central axis of the cylindrical member FC.

[0040] Therefore, by the first base BS1 abutting at least at different first contact points, second contact points, and third contact points on the first surface, the straight line CL perpendicular to the first surface can be aligned with the rotation axis of the cutting portion CT at the position of the hole portion HL.

[0041] The guide GD is provided with an insertion hole into which the pilot PL is inserted, and is arranged on the side of the second surface. For example, the guide GD may be formed of a spherical bearing, and the central axis of the hole HL may pass through the center of the spherical surface of the spherical bearing, and the spherical surface of the spherical bearing may be configured to abut against the opening of the hole HL.

[0042] By inserting the pilot PL into the insertion hole of the guide GD with the spherical surface of the spherical bearing abutting against the opening of the hole HL, the intersection of the line CL and the central axis of the insertion hole of the guide GD can be positioned relative to the hole HL. As a result, the rotation axis of the cutting part CT of the cutting tool DR can be positioned so that it passes through the center of the opening on the second surface side of the cylindrical member FC. In addition, it is possible to reduce friction that occurs on the second surface side of the inner surface of the hole HL when the cutting part CT cuts the inner surface of the hole HL.

[0043] The inner diameter of the insertion hole provided in the guide GD may be smaller than the inner diameter of the hole HL. The inner diameter of the insertion hole may be the same as or approximately the same as the outer diameter of the pilot PL so that the pilot PL can be inserted into the insertion hole provided in the guide GD.

[0044] The second base BS2 supports the guide GD while allowing the central axis of the insertion hole provided in the guide GD to swing, and abuts the guide GD against the opening of the hole HL. The second base BS2 positions the intersection of the line CL and the central axis of the insertion hole of the guide GD relative to the hole HL.

[0045] [Procedure of Supporting Method] FIG. 3 is a flowchart of a supporting method for a cutting tool according to an embodiment of the present disclosure.

[0046] In step S101, the cylindrical member FC is disposed between the first base BS1 and the second base BS2.

[0047] In step S103, the first base BS1 is brought into contact with the first surface of the cylindrical member FC.

[0048] In step S105, the guide GD is brought into contact with the second surface of the cylindrical member FC. At this time, the second base BS2 supports the guide GD while allowing the central axis of the insertion hole provided in the guide GD to swing, and the guide GD is brought into contact with the opening of the hole portion HL. Note that steps S103 and S105 can be performed in any order. Unlike the flowchart shown in FIG. 3, step S103 may be performed after step S105.

[0049] In step S107, the pilot PL is inserted into the insertion hole of the guide GD.

[0050] In step S109, with the pilot PL inserted into the insertion hole of the guide GD, the cutting part CT is inserted into the hole HL. Thereafter, the cutting part CT cuts the inner surface of the hole HL to enlarge the diameter of the hole HL.

[0051] Effect of the embodiment As described in detail above, the support jig for a cutting tool according to the present disclosure supports a cutting tool that expands the diameter of a hole that penetrates from a first surface to a second surface of a cylindrical member. The cutting tool includes a cutting portion and a pilot. The cutting portion is inserted into the hole from the first surface side and cuts the inner surface of the hole. The pilot is provided on the rotation axis of the cutting portion, at the tip of the cutting portion, with the insertion direction of the cutting portion into the hole as a reference. The support jig includes a first base, a guide, and a second base. The first base abuts against the first surface and aligns the rotation axis of the cutting portion with a line perpendicular to the first surface at the position of the hole. The guide has an insertion hole into which the pilot is inserted and is arranged on the second surface side. The second base supports the guide while allowing the central axis of the insertion hole to swing, and abuts the guide against the opening of the hole.

[0052] This reduces the cost and labor required to accurately expand the diameter of the hole that penetrates the cylindrical member in the radial direction. For example, a machining center for holding the cylindrical member FC while maintaining the circularity of the cylindrical member FC is not required. The cutting tool can be oriented to match the direction of the hole without maintaining the circularity of the cylindrical member FC, allowing the hole to be expanded accurately while reducing cost and labor.

[0053] The first base may contact at least a first contact point, a second contact point, and a third contact point that are different from each other on the first surface. The first contact point and the second contact point may have the same distance to a line when projected onto a plane perpendicular to the central axis of the cylindrical member. The position of the third contact point may be different from the positions of the first contact point and the second contact point along the central axis of the cylindrical member. This allows the line perpendicular to the first surface to coincide with the rotation axis of the cutting part at the position of the hole. As a result, the diameter of the hole can be expanded with high precision.

[0054] The second base may be configured to position the intersection of the straight line and the central axis of the insertion hole relative to the hole. This prevents the pilot and cutting part from damaging the inner surface of the hole on the second surface side. As a result, it is possible to machine the inner surface of the hole while taking into consideration the material of the second surface side. Furthermore, it is possible to reduce friction occurring on the second surface side of the inner surface of the hole.

[0055] The guide may be configured with a spherical bearing, the central axis of the insertion hole passing through the center of the spherical surface of the spherical bearing, and the spherical surface abutting against the opening. This allows the intersection of a line perpendicular to the first surface at the position of the hole and the central axis of the insertion hole of the guide to be positioned relative to the hole. As a result, the rotation axis of the cutting part of the cutting tool can be positioned to pass through the center of the opening on the second surface side of the cylindrical member.

[0056] The inner diameter of the insertion hole may be smaller than the inner diameter of the hole portion, which allows the pilot inserted into the insertion hole to pass through the hole portion, thereby preventing the pilot from damaging the inner surface of the hole portion.

[0057] The cutting tool may further include a moving unit provided on the first base for moving the cutting unit so that the cutting unit cuts a range of the inner surface from the first surface to a predetermined depth, thereby improving the efficiency of work using the cutting tool.

[0058] The predetermined depth may be shorter than the length of the hole from the first surface to the second surface. This prevents the pilot and cutting part from damaging the inner surface of the hole on the second surface side. As a result, it is possible to machine the inner surface of the hole while taking into consideration the material on the second surface side.

[0059] The material of the first surface side of the cylindrical member may be different from the material of the second surface side. The material of the second surface side of the cylindrical member may be a composite material. The material of the first surface side of the cylindrical member may be aluminum or an aluminum alloy. In this way, the cutting tool DR used to machine a cylindrical member made of two or more types of materials can be held by a support jig.

[0060] The outer peripheral surface of the cylindrical member may be the first surface, and the inner peripheral surface of the cylindrical member may be the second surface, thereby allowing the diameter of the hole to be enlarged from the outer peripheral surface of the cylindrical member using a cutting tool.

[0061] The cutting tool supporting method according to the present disclosure includes disposing a cylindrical member between a first base and a second base, abutting the first base against a first surface, abutting the guide against the second surface, and inserting a cutting part into the hole with a pilot inserted into the insertion hole, thereby reducing the cost and labor required to accurately expand the diameter of the hole that penetrates the cylindrical member in the radial direction.

[0062] According to the present disclosure, it is possible to reduce the cost and labor required to accurately expand the diameter of a hole that penetrates the radial direction of a cylindrical member, thereby improving work efficiency. As a result, it is possible to contribute to, for example, Goal 8 of the Sustainable Development Goals (SDGs) led by the United Nations, which is to "Promote inclusive and sustainable economic growth, full and productive employment and decent work for all."

[0063] Although several embodiments have been described, the embodiments can be modified or varied based on the above disclosure. All components of the above embodiments and all features described in the claims may be individually extracted and combined, unless they are mutually inconsistent.

[0064] The entire contents of Japanese Patent Application No. 2024-044701 (filing date: March 21, 2024) are incorporated herein by reference.

[0065] AR1, AR2 Direction BS1 First base BS2 Second base CL Straight line CT Cutting part D1, D2 Distance DR Cutting tool FC1 Outer peripheral surface material FC2 Inner peripheral surface material FC Cylindrical member GD Guide HL Hole part ME Balancer MH Moving part PD1, PD2, PD3 Contact part PL Pilot

Claims

1. A support jig for a cutting tool that enlarges the diameter of a hole that penetrates from a first surface to a second surface of a cylindrical member, wherein the cutting tool comprises: a cutting section that is inserted into the hole from the side of the first surface and cuts the inner surface of the hole; and a pilot that is provided at the tip of the cutting section and on the rotation axis of the cutting section, with the direction of insertion of the cutting section into the hole as a reference; and the support jig comprises: a first base that abuts against the first surface and aligns a line perpendicular to the first surface at the position of the hole with the rotation axis of the cutting section; a guide that is provided on the side of the second surface and has an insertion hole into which the pilot is inserted; and a second base that supports the guide while allowing the central axis of the insertion hole to swing, and abuts the guide against the opening of the hole.

2. The support jig described in claim 1, wherein the first base abuts at least at different first, second and third contact points on the first surface, the first and second contact points have equal distances to the straight line when projected onto a plane perpendicular to the central axis of the cylindrical member, and the position of the third contact point is different from the position of the first and second contact points along the central axis of the cylindrical member.

3. A support jig as described in claim 1, wherein the second base positions the intersection of the straight line and the central axis of the insertion hole relative to the hole portion.

4. A support jig as set forth in claim 1, wherein the guide is constituted by a spherical bearing, the central axis of the insertion hole passes through the center of the spherical surface of the spherical bearing, and the spherical surface abuts against the opening.

5. A support jig as set forth in claim 1, wherein the inner diameter of the insertion hole is smaller than the inner diameter of the hole portion.

6. The support jig described in claim 1, further comprising: a moving unit provided on the first base for moving the cutting unit so that the cutting unit cuts the range of the inner surface from the first surface to a predetermined depth.

7. A support jig as set forth in claim 6, wherein the predetermined depth is shorter than the length of the hole from the first surface to the second surface.

8. A support jig according to claim 1, wherein the material of the first surface side of the cylindrical member is different from the material of the second surface side.

9. The support jig according to claim 8, wherein the material on the second surface side of the cylindrical member is a composite material.

10. A support jig as set forth in claim 8, wherein the material on the side of the first surface of the cylindrical member is aluminum or an aluminum alloy.

11. A support jig as set forth in claim 1, wherein the outer peripheral surface of said cylindrical member is the first surface, and the inner peripheral surface of said cylindrical member is the second surface.

12. A method for supporting the cutting tool using the support jig according to any one of claims 1 to 11, comprising: arranging the cylindrical member between the first base and the second base; abutting the first base against the first surface and abutting the guide against the second surface; and inserting the cutting part into the hole with the pilot inserted into the insertion hole.

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