JP4698891B2 - Drilling tool - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
According to the present invention, a cutting edge tip is provided on the outer periphery of the tip of a tool body having a cutting edge at the tip through a cartridge, and the opening of the processing hole is formed in accordance with the formation of the processing hole by the cutting blade. The present invention relates to a drilling tool capable of deburring and chamfering.
[0002]
[Prior art]
As this type of drilling tool, a cutting blade is provided facing the tip of the chip discharge groove formed on the outer periphery of the tool body rotated about the axis, and the chip discharge groove is provided in the circumferential direction of the tool body. A mounting groove is formed on the tool tip side of the land defined in parallel to the above-mentioned axis, and a cutting blade tip held by the cartridge is mounted on the outer peripheral surface of the tool body so as to be able to protrude and retract in this mounting groove. Has been proposed. Further, the inventors of the present invention disclosed in JP-A-11-309604 and JP-A-11-320228 in that the cartridge is mounted on a base fixed to the tool body and an arm rotatably attached to the base. The cutting edge tip is attached to the tip of this arm, and an urging member (torsion coil spring) is interposed between the arm and the base to urge the arm by the urging force, Proposes a blade tip that can be moved freely.
[0003]
[Problems to be solved by the invention]
By the way, the amount of chamfering and deburring by such a drilling tool varies depending on the cutting conditions and cutting environment.For example, when deburring a workpiece that is likely to generate large burrs, or when it is desired to increase the chamfering amount. The urging force of the urging member when the cutting edge chip bites into the opening of the processing hole must be set to be strong. Conversely, when the workpiece is made of a soft material or when the amount of chamfering is to be reduced, the urging force of the urging member is weakened so that the cutting edge tip is too strong. You must keep it out of the opening. However, in the conventional drilling tool, the biasing member is fixed between the arm and the base so as to be incorporated in the cartridge, and such a cartridge is accommodated in the mounting groove. Therefore, if you want to adjust the biasing force of the biasing member in this way, remove the cartridge from the tool body, disassemble the arm and base, and bias the biasing member. It is necessary to replace the cartridges with different ones, or to prepare multiple types of cartridges with biasing members with different biasing forces in advance. This requires an urging member and a cartridge, which is inefficient and uneconomical.
[0004]
The present invention has been made under such a background. In the above-described drilling tool provided with the cutting edge tip for chamfering or deburring, the cartridge and the biasing member are exchanged or a plurality of types are prepared. An object of the present invention is to provide a drilling tool that can adjust the amount of chamfering and the amount of deburring.
[0005]
[Means for Solving the Problems]
In order to solve the above problems and achieve such an object, the present invention provides a tool body having a cutting edge at the tip and a support groove attached to a mounting groove formed on the outer periphery of the tip of the tool body. A cartridge rotatably supported around an axis, a cutting edge chip provided on the cartridge and capable of protruding and retracting from the outer peripheral surface of the tool body as the cartridge rotates, and the mounting groove of the cartridge A biasing member that is interposed on the bottom surface side and biases the cartridge toward the outer peripheral side of the tool; and a biasing force adjusting means that adjusts the biasing force of the biasing member, wherein the biasing member is in a compressed state. The both ends are elastic bodies that urge the cartridge by abutting against the cartridge and the bottom surface side of the mounting groove, and the urging force adjusting means is provided so as to be able to protrude and retract on the bottom surface side of the mounting groove. With the above A first biasing force adjusting member that abuts on one end of the member, that provided retractably in the cartridge and a second biasing force adjusting member that contacts the other end of the biasing member Features. Therefore, according to such a drilling tool, by adjusting the urging force of the urging member by the urging force adjusting means, the cutting edge tip can be processed without changing the cartridge or the urging member itself. It is possible to increase / decrease the strength when biting into the opening, and to optimize the chamfering amount and the deburring amount according to the cutting conditions and the cutting environment.
[0006]
The urging member is an elastic body that urges the cartridge by pressing both ends of the urging member against the cartridge and the bottom surface side of the mounting groove in a compressed state like the torsion coil spring, for example. Te, the urging force adjusting means includes a first biasing force adjusting member provided retractably to the bottom side of the mounting groove in contact with one end portion of the biasing member, provided retractably in the cartridge comprise a second biasing force adjusting member that contacts the other end of the biasing member, in this way by infested with first, second biasing force adjusting member, the biasing consisting elastic body Since the compression state of the member is adjusted and the urging force at the time of initial biting into the opening of the machining hole is changed, the first and second of these are adjusted according to the cutting conditions and the cutting environment as described above. Of the biasing force adjustment member By adjusting the, it is possible to set the optimal biasing force.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4 show an embodiment of the present invention. In the present embodiment, the tool body 1 has a substantially cylindrical shape with the axis O as the center, and the outer periphery of the tip thereof is located behind the tool rotation direction T around the axis O toward the tool rear end side. A pair of chip discharge grooves 2, 2 twisted to the side is formed so as to open to the front end surface 3 of the tool body 1 and extend to the rear end side, and the tool rotation direction T of these chip discharge grooves 2, 2. A tip 4 made of a hard material such as cemented carbide is brazed and attached to the tip of the wall surface facing the side, and a cutting edge 5 is formed at the tip of the tip 4 for drilling a machining hole in the work material. Has been. In the tool body 1, a supply hole 6 for cutting fluid or the like is formed along the axis O from the rear end side to the front end side of the tool, and the supply hole 6 branches into two on the tool front end side. And extending in parallel with the axis O and opening at the tip surfaces 3 and 3 connected to the cutting edges 5 and 5 on the rear side in the tool rotation direction T.
[0008]
One of a pair of lands 7, 7 defined between the chip discharge grooves 2, 2 in the circumferential direction of the tool body 1 is located on the tool rear end side from the tip surface 3 connected to the land 7. A mounting groove 8 is formed at a slightly separated position, and a cartridge 9 is accommodated and mounted in the mounting groove 8. Here, the mounting groove 8 extends to the rear end side of the tool in parallel to the axis O, and is recessed to the inner peripheral side in the radial direction with respect to the axis O and opened to the outer peripheral side in a cross-sectional view orthogonal to the axis O. The groove bottom surface 8A is deepest on the tip side (left side in FIG. 3) of the tool body 1 as shown in FIG. A stepped portion 8B having a shallow depth of one step groove is formed at a substantially central portion in the longitudinal direction of the mounting groove 8 on the end side (right side in FIG. 3), and a pedestal in which the depth of another step groove is further reduced at the rear end side. A portion 8C is formed. Then, the stepped portion 8B of the groove bottom surface 8A has a long screw shape screwed so as to penetrate the tool main body 1 in the diameter direction at the tip side thereof, that is, the substantially central portion of the mounting groove 8 in the longitudinal direction. The front end portion of the first urging force adjusting member 10 is protruded, and this first urging force adjusting member 10 is one of the urging force adjusting means in the present embodiment. Further, a pin-like support shaft 11 is inserted into one land 7 in which the mounting groove 8 is formed so as to extend in a tangential direction of a circle centering on the axis O perpendicular to the longitudinal direction of the mounting groove 8. As shown in FIG. 3, the front end portion of the support shaft 11 is slightly on the front end side and the outer peripheral side (upper side in FIG. 3) than the pedestal portion 8C on the rear end side of the mounting groove 8 as shown in FIG. The groove wall surfaces 8D and 8D of the mounting groove 8 that stand up from the groove bottom surface 8A and face the circumferential direction of the tool body 1 are projected so as to be orthogonal to the groove wall surfaces 8D and 8D.
[0009]
On the other hand, the cartridge 9 attached to the attachment groove 8 is formed so as to extend in parallel with the axis O in accordance with the attachment groove 8, and a tip attachment seat 9A is formed at the tip thereof. A cutting edge tip 12 for deburring and chamfering the peripheral edge of the opening of the machining hole is detachably attached to the tip mounting seat 9A by a clamp screw 13, and a mounting hole 9B is provided through the rear end portion. The cartridge 9 is rotatably supported around the support shaft 11 by fitting the tip end portion of the support shaft 11 protruding between the groove wall surfaces 8D and 8D of the mounting groove 8 into the mounting hole 13. . However, the rotation of the cartridge 9 is caused by the contact portion 9C facing the inner peripheral side of the tool body 1 (lower side in FIG. 3) at the rear end portion of the cartridge 9 on the rear end side with respect to the mounting hole 9B. 3 is in contact with the pedestal portion 8C of the groove bottom surface 8A so that the tip of the cartridge 9 is rotated from the state shown in FIG. 3 toward the outer peripheral side of the tool body 1 (centering on the support shaft 11 in FIG. 3). Rotation in the clockwise direction) is restricted. The cutting edge tip 12 is formed into a substantially equilateral triangular (strictly hexagonal) flat plate shape by a hard material such as cemented carbide, and the rear end portion 9C of the cartridge 9 abuts against the pedestal portion 8C. In this state, as shown in FIG. 3, one corner of the equilateral triangle (one short side of the eccentric hexagon) is attached to the tip mounting seat 9 </ b> A so as to protrude to the outer peripheral side of the tool body 1, Cutting blades 12A formed on the side ridges of the equilateral triangle that can be sunk into the mounting groove 8 by the rotation of the cartridge 9, that is, can be sunk into and out of the outer peripheral surface of the tool body 1 and intersect the corners. , 12A is used to deburr or chamfer the processed hole.
[0010]
Further, the inner peripheral side of the tool body 1 is released between the tip end portion of the cartridge 9 where the tip mounting seat 9A is formed and the rear end portion where the mounting hole 9B and the contact portion 9C are formed. In addition, a recess 9E in which a top plate portion 9D is formed is formed on the outer peripheral side, and a spring support pin 9F is formed integrally with the cartridge 9 so as to extend in parallel with the mounting hole 9B in the recess 9E. Thus, the spring support pin 9F is loosely inserted and attached so that the torsion coil spring 14 is wound as an urging member in the present embodiment. The torsion coil spring 14 protrudes from the inner peripheral side of the tool body 1 of the recess 9 </ b> E whose one end is released and protrudes from the stepped portion 8 </ b> B of the mounting groove 8. The other end of the cartridge 9 is brought into contact with the top plate 9D, and is compressed when the two ends are in contact with each other. In a state where the abutting portion 9C abuts on the base portion 8C and the cutting edge tip 12 protrudes from the outer peripheral surface of the tool body 1, the cutting edge tip 12 is elastically biased in a direction protruding toward the outer peripheral side. . Further, the second urging force adjusting member 15 having a short screw shape penetrates the top plate portion 9D vertically at a position where the other end portion of the torsion coil spring 14 contacts the top plate portion 9D. The second urging force adjusting member 15 is another one of the urging force adjusting means in this embodiment.
[0011]
In the drilling tool configured as described above, the tool body 1 is advanced while rotating around its axis O, so that a machining hole is formed in the workpiece by the cutting blades 5 and 5 provided at the tip thereof. Then, the opening of the machining hole is deburred by the cutting edge 12A facing the front end side of the cutting edge tip 12 protruded from the front end side of the tool main body 1 slightly on the rear end side from the front end of the tool main body 1. And chamfering is performed. When the tool body 1 is further advanced, the cutting edge tip 12 is pushed into the inner periphery of the machining hole, so that the cartridge 9 is centered on the support shaft in FIG. 3 against the urging force of the torsion coil spring 14. When the machining hole is a through hole, the cartridge 9 is biased by the torsion coil spring 14 when the machining hole is pulled out. Accordingly, the cutting edge tip 12 protrudes again by rotating in the opposite direction, and the opening of the processing hole at the time of removal is deburred or chamfered by the cutting edge 12A facing the rear end side.
[0012]
Thus, in the deburring and chamfering of the machining hole opening by such a cutting edge tip 12, when the deburring amount and the chamfering amount are changed depending on the cutting conditions such as the material of the workpiece and the cutting environment, the above-described drilling is performed. In the tool, the support shaft 11 is removed and the cartridge 9 is detached and disassembled as in the prior art, and the torsion coil spring 14 is replaced with one having a different spring constant, or a torsion coil spring 14 having a different spring constant is attached in advance. By operating the first urging force adjusting member 10 or the second urging force adjusting member 15 as the urging force adjusting means without changing to another cartridge 9, the cutting blade of the cutting edge tip 12 is operated. The strength when 12A bites into the processed hole opening can be adjusted, and the deburring amount and the chamfering amount can be easily changed. That is, if the first and second biasing force adjusting members 10 and 15 having a screw shape are screwed into the torsion coil spring 14 side, the contact portion 9C of the cartridge 9 is in contact with the pedestal portion 8C. The torsion coil spring 14 is more strongly compressed, and therefore the urging force that urges the cartridge 9 so that the cutting blade tip 12 protrudes to the outer peripheral side also increases. Therefore, the cutting blade tip 12 is resisted against this urging force. A large force is required to immerse the entire cartridge 9, and as a result, the deburring amount and the chamfering amount can be increased. Moreover, if these 1st, 2nd urging | biasing force adjustment members 10 and 15 are loosened, the deburring amount and chamfering amount can be made small conversely.
[0013]
Therefore, according to the drilling tool, by adjusting the first and second urging force adjusting members 10 and 15 as the urging force adjusting means in this way, the cartridge 9 and the torsion coil spring 14 as the urging member can be moved. The amount of deburring and chamfering can be adjusted easily without removing and replacing them, or preparing multiple types of cartridges 9 and torsion coil springs 14 in advance. It can be reduced and is efficient, and it is economical because it is not necessary to prepare extra parts. In addition, in the present embodiment, the first and second urging force adjusting members 10 and 15 are screw-shaped, and the amount of protrusion and withdrawal to the torsion coil spring 14 side is changed in accordance with the screwing amount of the torsion coil spring 14. The compression state can be adjusted to a non-continuous floor, and therefore the deburring amount and chamfering amount can be optimally adjusted according to the cutting conditions and cutting environment.
[0014]
The first screw-like as in the present embodiment, the case of providing a second biasing force adjusting member 10 and 15, these thread pitch as different, e.g., a first biasing force adjusting member elongated If the screw pitch of 10 is made larger than that of the short second biasing force adjusting member 15, the rough biasing force is adjusted by the first biasing force adjusting member 10 having a large pitch, while the fine adjustment is performed by the first biasing force adjusting member 10 having a small pitch. It is also possible to make adjustments such as by using the second urging force adjusting member 15. In the present embodiment, the first and second urging force adjusting members 10 and 15 are both screw-shaped, but the particularly long first urging force adjusting member 10 protrudes from the step portion 8B. Then, the tip of the torsion coil spring 14 that is in contact with one end of the torsion coil spring 14 is inserted into the tool body 1 in the form of a pin, and the amount of protrusion and depression may be adjusted by a screw screwed from the outer peripheral surface side of the land 7 of the tool body 1. . Further, the biasing member may be a coil spring or a disc spring other than the torsion coil spring 14, that is, when both ends thereof are in contact with the cartridge 9 and the groove bottom surface 8 A side of the mounting groove 8 in a compressed state. Any elastic body that biases the cartridge 9 may be used.
[0015]
【The invention's effect】
As described above, according to the present invention, the cartridge of the biasing member can be efficiently and economically replaced without replacing the cartridge or the biasing member or preparing a plurality of types of cartridges or biasing members. The urging force can be adjusted, and the optimum deburring amount and chamfering amount can be set according to the cutting conditions and cutting environment.
[Brief description of the drawings]
FIG. 1 is a side view showing an embodiment of the present invention.
FIG. 2 is a front view of the embodiment shown in FIG. 1 as viewed from the front end side.
FIG. 3 is an enlarged cross-sectional view of a mounting groove 8 portion of the embodiment shown in FIG.
4 is an enlarged view of the mounting groove 8 portion of the embodiment shown in FIG. 1 as viewed from the outer peripheral side of the tool body 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tool main body 5,12A Cutting edge 8 Mounting groove 8A Groove bottom face 8B of mounting groove 8 Step part 8C of groove bottom face 8A Base part 9 of groove bottom face 8A Cartridge 10 1st biasing force adjustment member (biasing force adjustment means)
11 Support shaft 12 Cutting edge tip 14 Torsion coil spring (biasing member)
15 Second urging force adjusting member (urging force adjusting means)

Claims (1)

A tool main body having a cutting edge at the tip, a cartridge attached to a mounting groove formed on the outer periphery of the tip of the tool main body and rotatably supported around a support shaft, and the cartridge provided in the cartridge A cutting edge tip that can be projected and retracted from the outer peripheral surface of the tool body as the tool rotates, and a biasing member that is interposed on the bottom surface side of the mounting groove of the cartridge and biases the cartridge toward the tool outer peripheral side. And an urging force adjusting means for adjusting the urging force of the urging member, and the urging member is in a compressed state when both ends thereof abut against the cartridge and the bottom surface side of the mounting groove. An elastic body for urging the cartridge, wherein the urging force adjusting means is provided on the bottom surface side of the mounting groove so as to be able to project and retract, and is in contact with one end of the urging member; Cart Drilling tool, characterized in that provided retractably and a second biasing force adjusting member that contacts the other end of the biasing member.

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