JPS61236411A - Chamfering device of drilled part - Google Patents

Abstract

PURPOSE:To enable a drilled part to be chamfered by one shuttle motion through an outer cylinder, bearings rotatable inside the outer cylinder, spindle rotatable and slidable in the axial line and a tool holder swivelably actuating its point end, in the case of a chamfering device of the drilled part. CONSTITUTION:When a spindle 10 is advanced while it rotates, an outer cylinder 21 and a front cylinder 28 advance with no rotation by ball bearings 18, 19, 20, and a chamfering device, stopping the cylinder if it is adapted to a work 3, advances only the spindle 10. Here a cam surface 13a of the spindle 10 is adapted to an inner ring 19a of the bearing, and the device, depressing the spindle 10 in the inward radial direction while displacing outward a tool fixed to the end of a tool holder 11 to be adapted to a hole 3a, chamfers a hole part. If the spindle 10 is retracted, the tool automatically returns to the original position by a spring 14. The device presets the contact timing of the cam surface 13a and its tilt angle. In this way, the device, chamfering the drilled part by one time shuttle turning, improves finishing and a life of the tool.

Description

Detailed Description of the Invention (Industrial Application Field) This invention provides a method for chamfering the drilled portion to remove warping that occurs on the opposite periphery of the hole in the workpiece after drilling a hole in the workpiece. It is related to the device.

(Prior Art) As shown in FIG. 7, a conventional chamfering device for a perforation has a cutting tool 2 attached to the tip of a drive spindle l that is formed to be slidable in the axial direction and rotatable around the axis. As shown by the two-dot chain line, it is installed so that it can stand up at right angles, and with the tool 2 laid down horizontally, the drive spindle 1 is moved toward the front side ( After the cutting tool 2 comes out to the other side of the hole 3a, the cutting tool 2 is erected at right angles as shown in the figure, and then the drive spindle 1 is rotated and retreated, thereby opening the hole 3a. The turn 3b on the opposite periphery was removed (
(See Figure 8). After chamfering is completed, the drive spindle 1 is moved forward again to separate the cutting tool 2 from the workpiece 3.
The cutting tool 2 was brought down to its original state and moved backward, and the cutting tool 2 was allowed to escape from the hole 3a of the workpiece 3.

(Problems to be Solved by the Invention) In order to chamfer one hole 3a, the drive spindle l advances, the cutting tool 2 rises, the drive spindle l retreats to cut the return 3b, and the drive spindle 1 moves forward again. , a total of six operations, including lowering of the cutting tool 2 and retraction of the drive spindle 1, were required, resulting in low efficiency. In addition, since the cutting edge 2a of the cutting tool 2, which is inclined at 45 degrees with respect to the center line of the hole 3a, is pressed firmly against the periphery of the opposite side of the hole 3a for cutting, the cutting resistance becomes large and the cutting edge 2a is easily worn out. There were problems such as the occurrence of other curls in the marks.

(Means for Solving the Problems) The present invention includes an outer cylinder 21 that is fixed at a predetermined position on the center line of a hole drilled in a workpiece, and an outer cylinder 21 that is rotatably provided inside the outer cylinder 21. A ring 19a, a spindle IO provided slidably along the axis of the ring 19a and rotatable with respect to the axis, and a pin 12 with an intermediate portion at the tip of the spindle IO that swings in the diametrical direction. The tool holder 11 is freely supported, has a chamfering tool 15 fixed to its tip, and has an upwardly inclined cam surface 13a formed at its rear end to press against the inner corner of the rear end of the ring 19a. By moving the spindle 10 forward with respect to the outer cylinder 21, the inclined cam surface 13a of the tool holder 11 comes into contact with the ring 19a, and the tip of the tool holder 11 is displaced radially outward. It is.

(Function) When the outer cylinder 21 is fixed at a predetermined position on the center line of the hole 3a previously drilled in the workpiece 3, and then the spindle IO is moved forward while rotating, the outer cylinder 21 is connected to the front end of the spindle IO. The inclined cam surface 13a at the rear end of the swingable tool holder 11 contacts the inner corner of the rear end of the ring 19a installed in the outer cylinder 21 and is pushed down radially inward, so that the tool holder 11 is the hole 3a of the workpiece 3
The cutting tool 15, which is inclined with respect to the center line of the cutting tool holder 11 and fixed to the tip of the cutting tool holder 11, is displaced radially outward and rotates with its cutting edge touching the inner surface of the hole 3a. Therefore, by appropriately setting the fixing position of the outer cylinder 21, the timing of contact between the inclined cam surface 13a at the rear end of the tool holder and the ring 19a, the inclination angle of the inclined cam surface 13a, etc., the above-mentioned problem can be achieved. As the spindle 10 advances, the cutting edge of the cutting tool 15 gradually displaces outward to turn the peripheral edge of the workpiece 3 on the opposite side of the hole 3a into a cone shape. That is, it is chamfered by turning. The shape of the cone in this case is determined by the distance from the fulcrum of the cutting tool holder 11 to the cutting edge and the inclined cam surface 13a at the rear end of the cutting tool 15, and the inclination angle of the inclined cam surface 13a. Then, when the spindle lO is moved backward, the contact area between the inclined cam surface 13a at the rear end of the tool holder II and the ring 19a moves from the high part of the inclined cam surface 13a to the lower part, so that the cutting edge of the cutting tool 15 is placed in the hole. 6 (Embodiment) In FIG. 1, the spindle 10 is automatically returned to the center side.
It slides along the center line of the tool holder 11 and rotates around the center line, and has a bifurcated portion 10a formed at its tip (see Fig. 2). A plate-shaped portion 11a is inserted, and this plate-shaped portion 11a is swingably connected to the tip of the bifurcated portion 10a of the spindle 10 with a pin 12. The plate-shaped portion 11a of the tool holder 11 has a plate cam 13 (see Fig. 4) protruding from the rear end of the upper surface thereof, which has an upwardly inclined cam surface 13a, and a plate cam 13 (see Fig. 4) having a rearwardly upwardly inclined cam surface 13a on the opposite lower surface. An inclined surface 11b is formed. The base tob of the bifurcated portion 10a of the spindle 1G is inclined approximately parallel to the gently sloped surface 11b of the tool holder 11 with a slight gap, and the compression coil spring 14 is inserted into the pocket 10c bored in the base 10b. The compression coil spring 14 urges the tool holder 11 counterclockwise. On the other hand, the distal end portion of the tool holder 11 is formed into a cylindrical shape that is slightly thinner than the spindle 10, and a top-shaped chamfering vise (see Fig. 3) protrudes from the distal end of the spindle 10. It is fixed by a set screw 16 so that the length can be adjusted.

An outer fi 21 is attached to the above spindle 10 via three radial ball bearings ta, tq, and 20 to the front portion of a flange 17 fixed slightly rearward of the forked portion 10a. That is, the first radial ball bearing 18 is loosely fitted so that its inner ring 18a can slide on the distal end side of the bifurcated portion 10a of the spindle IO, and its outer ring tab is fixed to the inner surface of the outer cylinder 21. . In addition, the second radial ball bearing 1
9 is loosely fitted near the base of the bifurcated portion 10a of the spindle 10 so that the rear end of the inner ring 19a contacts the plate cam 13 of the tool holder 11, and the outer ring 19b is fixed to the inner surface of the outer cylinder 21. Further, the third radial ball bearing 20 is fixed to the spindle 10 so that the inner ring 20a is in contact with the flange 17, and the outer ring 20b is loosely fitted into the outer cylinder 21 so as to be slidable.

Note that a ring-shaped spacer 22 is interposed between the outer ring 18b of the first radial ball bearing 18 and the outer ring 19b of the second radial ball bearing 19, and the inner ring 19a of the second radial ball bearing 19
A disk 23, a return spring 24, and a spring holder 25 are interposed between the spring bearing and the inner ring 20a of the third radial ball bearing 20. At the rear end of the outer cylinder 21, a third
A stop ring 26 that locks the outer ring 20b of the radial ball bearing 20 is fixed, and a detent 21a that is slidably fitted to the horizontal guide bar 27 is protruded from the upper surface of the rear end, and a stop ring 21a is provided at the tip. , the front cylinder 28 is fixed so as to extend the outer cylinder 21 forward.

In the above structure, when the spindle 10 is rotated and moved forward, the spindle lO, the tool holder 11, and the chamfering tool 15 move forward while rotating together, and the inner ring 20a of the third radial ball bearing 20 and the spring holder 25, return spring 24, spring holder is disk 23
, second radial ball bearing 19. The outer cylinder 21 and the front cylinder 28 move forward without rotating via the first radial ball bearing 18. When the tip of the front cylinder 2B comes into contact with the front surface of the workpiece 3, the front cylinder 28 and the outer cylinder 21 come to rest, and from then on the spindle 10. Only the tool holder 11 and the chamfering tool 15 move forward. however.

The protruding length of the front cylinder 28 and the chamfering tool 15 is adjusted so that when the outer cylinder 21 stops, the cutting edge of the chamfering tool 15 is located close to the periphery on the opposite side (left side in FIG. 1) of the hole 3a of the workpiece 3. The height is set. Therefore, when the spindle 10 moves forward while rotating further.

As shown in FIG. 4, the inner ring 1 of the second radial ball bearing 19
9a acts as a ring for tilting the tool holder 11, and the chamfering tool 15 is attached to the hole 3a of the workpiece 3.
It is pressed near the periphery on the opposite side, and turning begins and one chamfering is performed.

In addition, in the above embodiment, the outer cylinder 21 is moved forward by the spindle 10, and the tip of the front cylinder 28 is brought into contact with the surface of the workpiece 3 to position the outer cylinder 18. Therefore, the outer cylinder 21 can be moved easily and easily. Accurate positioning is possible. Additionally, a radial ball bearing 18.1 is provided between the spindle IO and the outer cylinder 18.
Since 9.20 is inserted, the run-out of the cutting tool 15 for single chamfering can be reduced. Furthermore, the second radial ball bearing 1
9 and the third radial ball bearing 20, the return spring 2
4 is interposed, so when the spindle 10 retreats after chamfering is completed.

The chamfering tool 15 is quickly separated from the turned part of the hole 3a of the workpiece 3 and returned to the center.

(Modification) In the above embodiment, as shown in FIG. A presser pin 29 is slidably inserted into the pin hole 10d so that its upper end contacts the inclined surface 11b of the tool holder 11, and its lower end contacts the front end of the inner surface of the inner ring 19a. In this case, the rattling of the cutting tool holder 11 disappears, and the finish of the chamfer marks becomes even better.

Further, as shown in FIG. 6, a workpiece 3 is attached to the tip of the front cylinder 28.
By forming a stepped portion 28a that engages with the peripheral edge of the hole 3a on the near side, the deflection of the front cylinder 28 and the outer cylinder 21 can be reduced, which is particularly suitable for chamfering a large diameter hole 3a.

(Effects of the Invention) Since chamfering is performed in the process of advancing the chamfering tool into a hole drilled in the workpiece, the chamfering work is completed by just one reciprocation of the chamfering tool. Therefore, efficiency is doubled compared to the conventional device, which required the chamfering tool to be moved back and forth twice for one chamfering. In addition, since the above-mentioned chamfering is done by turning, the cutting resistance is reduced compared to conventional chamfering, and the finish of the cut surface is improved.
Moreover, the life of the chamfering tool is extended.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a plan view of the tool holder, FIG. 3 is a front view of the chamfering tool, and FIG. 4 is a longitudinal sectional view of the main parts when chamfering is completed. Fig. 5 is a vertical sectional view of the main part of a modified example, Fig. 6 is a longitudinal sectional view of the main part of another modified example, Fig. 7 is a side view of the conventional device, and Fig. 8 is a chamfered part of the conventional device. It is an explanatory diagram. 3: Workpiece, 3a: Hole, IO=Spindle, ] 1: Bit holder, 12: Pin, 13: Plate cam, 13a:
Inclined cam surface, 15: Chamfering tool, 19 Nirasial ball bearing, 19a: Inner ring (ring), 21: Outer cylinder. Patent Applicant Kyokuyo Kogyo Co., Ltd. Agent Patent Attorney Takeo Sakano 1) Completed Figure 1 Figure 2 Figure 3 Figure 5 316

Claims (1)

[Scope of Claims] [1] An outer cylinder fixed at a predetermined position on the center line of a hole drilled in a workpiece, a ring rotatably provided inside this outer cylinder, and an axis of this ring. A spindle is provided to be slidable along the axis and rotatable about this axis, and the middle part is supported swingably by a diametrical pin at the tip of the spindle, and a chamfering tool is attached to the tip. The tool holder is fixed and has a rear end inclined cam surface that is pressed against the inner corner of the rear end of the ring.
The drilling section is characterized in that by advancing the spindle with respect to the outer cylinder, the inclined cam surface of the tool holder comes into contact with the ring and the tip of the tool holder is displaced radially outward. Chamfering device. [2] The spindle is attached so that it can slide a minute distance relative to the outer cylinder and is urged backward by a spring, and the outer cylinder has a length that reaches slightly behind the chamfering tool. A chamfering device for a perforated portion according to claim 1. [3] The device for chamfering a perforated portion according to claim 2, wherein the tip of the outer cylinder is provided with a stepped portion that is engaged with the peripheral edge of the hole on the near side of the workpiece. [4] Any one of claims 1 to 3, wherein the ring is an inner ring of a radial ball bearing, the outer ring is fixed inside an outer cylinder, and a spindle is slidably inserted into the inner ring. A device for chamfering a perforated portion as described in .