JPH0533204Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention mainly relates to a face milling cutter that performs flat surface cutting of a workpiece, and more specifically to a face milling cutter that prevents chatter and vibration that occur in the workpiece. Regarding.

[Conventional technology]

In general, as a face milling cutter for cutting the surface of a workpiece, a plurality of grooves 2 are formed at the outer edge of the tip of a tool body 1 approximately on a disk, as shown in FIGS. 4 to 9. A throw-away chip 3 is installed in each of these grooves 2 by a wedge 5 that is tightened with a clamp screw 4, and a curved chip pocket 6 is formed on the forward side of each throw-away chip 3 in the direction of rotation. is,
Also, a tool body 1 is known in which a boss surface 7 is formed on the proximal end side, and a mounting hole 8 is formed in the center of the tool body 1. This face milling cutter is constructed by fitting the mounting hole 8 into the fitting shaft 12 of the arbor 11 mounted on the machine main shaft 9 via the key 10, and fastening with the tightening nut 13.
It is integrated into the main shaft 9 of the machine.

[Problem that the invention attempts to solve]

By the way, using the above conventional face milling cutter,
When machining mating surfaces of thin-walled parts with low geometrical rigidity, such as box-shaped workpieces, or machining markedly interrupted shapes, the width of the machined surface is determined by the distance between the pitch between one cutting edge and the next cutting edge. There are parts where the width is narrower than that, and when cutting such parts, there is a time when there is virtually no cutting (the number of teeth cutting at the same time is zero). The force fluctuations were large, which caused chatter and vibration. This chatter and vibration cause damage to the cutting edge and shorten its lifespan, and also cause a decrease in the machining accuracy of the workpiece, thereby impairing normal cutting.

Therefore, various face milling cutters have been proposed in an attempt to solve this problem (for example, see Japanese Patent Application Laid-Open No. 102614/1982 and Japanese Patent Application Laid-Open No. 102615/1982), but they have complicated structures, or There were still some aspects that could not be said to be sufficient, such as insufficient suppression of chatter and vibration.

This invention was made in view of the above circumstances,
The purpose of this is a face milling machine that can reliably suppress the occurrence of chatter and vibration in the workpiece material, perform normal cutting, and prevent damage to the cutting edge and decrease in machining accuracy. Our goal is to provide the following.

[Means for solving problems]

In order to achieve the above object, the present invention forms a recess at the center of the tip of the tool body, and provides a support member in the recess so as to be movable along the axis of the tool body. The work clamp member is rotatably provided around the axis of the tool body, and the tool body is provided with biasing means for protruding the support member toward the distal end of the tool body, and the tool body is attached to and detached from the arbor. A clamp mechanism that can be freely attached is provided between the tool body and the arbor.

[Effect]

In the face milling cutter of the present invention, a work clamp member is provided in a recess at the center of the tip of the tool body so as to be movable along the axis of the tool body via a support member and rotatable around the axis. The workpiece clamp member is caused to protrude toward the tip side of the tool body by the biasing means, and the workpiece being cut is held down by the workpiece clamp member.

Further, since the workpiece clamp member is attached to the center of the tip of the tool body, the tool body is attached to the arbor by a clamp mechanism.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3.

Reference numeral 20 in the figure is a tool body, and a plurality of grooves formed on the outer edge of the tip of this tool body 20 include
Each throw-away tip 21 is attached by a wedge 23 which is tightened by a clamp screw 22. A tip pocket 24 is formed in the tool body 20 on the front side in the rotational direction of each of the throw-away tips 21. Further, a substantially convex-shaped recess 25 is formed at the center of the tip of the tool body 20, and a work clamp member 26 is fitted into the recess 25 so as to be freely retractable. The tip end surface 26a of this work clamp member 26 is used as a contact surface against the workpiece 27, and is finished smoothly, and this tip surface 26a
A tapered portion 26b is formed at the peripheral edge of the holder.

The work clamp member 26 is formed so that its diameter is reduced stepwise (in three steps in FIG. 1) from the distal end side to the base end side, and the work clamp member 26 has a diameter that is reduced in steps (three steps in FIG. 1). A ring-shaped bearing case 28 is fitted between the tool body 20 and the inner circumferential wall of the recess 25 so as to be movable along the axis l of the tool body 20. The work clamp member 26 is rotatably supported by the bearing case 28 via a thrust ball bearing needle roller bearing 29 about the axis l of the tool body 20. Further, a retaining ring 30 is attached to the base end of the work clamp member 26.

A positioning screw 31 is provided in the through screw hole formed from the outer circumferential side of the tool body 20 to the recess 25.
is screwed in with its tip fitting into a keyway 28a formed at the outer edge of the tip of the bearing case 28. Furthermore, the through hole formed between the recess 25 and the base end surface of the tool body 20 includes:
The adjustment screw 32 is screwed in, and this adjustment screw 3
A spring pressing member 33 and a coil spring 34 are arranged between the bearing case 28 and the bearing case 28 . Then, the bearing case 28 in the recess 25 of the tool body 20 is regulated by the positioning screw 31 by the coil spring 34 whose biasing load is adjusted according to the screwing amount of the adjustment screw 32 into the tool body 20. With the bearing case 28 in the above position (before cutting starts and without the workpiece 27 in Fig. 1), the work clamp The distal end surface 26a of the member 26 is configured to protrude slightly beyond the axially most distal end of the throwaway tip 21.

Further, the tip of an arbor 35 is fitted into the attachment hole formed on the base end side of the tool body 20, and between the arbor 35 and the tool body 20, the tool body 20 can be attached to and removed from the arbor 35. A freely attachable clamping mechanism 36 is provided. This clamp mechanism 36 is a cutter clamper 3 fitted into a recess formed at the tip of the arbor 35.
7, a clamper spring 38 provided between the base end surface of the cutter clamper 37 and the arbor 35, and a substantially rectangular parallelepiped-shaped clamp head 39 formed at the tip of the cutter clamper 37;
A mounting hole 40 is provided at the bottom of the mounting hole of the tool body 20 and has an elongated inlet and a circular hole inside, and into which the clamp head 39 is removably fitted; 35, a cylindrical key 41 attached to the outer periphery of the distal end surface of the tool body 20, and a 1/4 circumference (90°) formed on the outer periphery of the proximal end surface of the tool body 20, and the key 41 The cutter clamper 37 is loosely fitted into the arc-shaped key groove 42 into which the cutter clamper 37 is fitted, and a pair of mounting holes formed in the arbor 35 opposite to the through hole are installed. The main components are a clamp bolt 43 and a clamp nut 44, and a steel ball 45 fitted into an insertion hole formed between the mounting hole in which the clamp bolt 43 is mounted and the outer periphery of the distal end surface of the arbor 35. ing. By engaging the key 41 and the keyway 42, the tool body 20 is rotated at approximately 90° with respect to the arbor 35 around its axis l.
The tool body 20 can be rotated by inserting the clamp head 39 of the cutter clamper 37 into the mounting hole 40 of the tool body 20.
By rotating the tool body 20 by 90 degrees, the tool body 20 and the cutter clamper 37 are brought into engagement with each other. Furthermore, by screwing the clamp bolt 43 into the clamp nut 44, the tapered part 43a of the head of the clamp bolt 43 and the tapered part 44a of the clamp nut 44 are connected to the tapered parts at both ends of the through hole of the cutter clamper 37. 37
a, 37b and the cutter clamper 3
7 is pushed upward in FIG. Furthermore, as the clamp bolt 43 moves outward along the mounting hole of the arbor 35, the steel ball 45 is pressed by the tapered portion 43b of the clamp bolt 43 and is pressed downward in FIG. It protrudes from the insertion hole of the arbor 35 to allow the tool body 20 to be removed from the arbor 35.

In addition, in FIG. 1, numerals 46 and 47 indicate a clamp bolt 43 and a clamp nut 44, respectively.
48 and 49 are retaining rings attached to the respective mounting holes in which the clamp bolt 43 and the clamp nut 44 are respectively mounted.

When cutting the workpiece 27 using the face milling cutter configured as described above, first, immediately after the start of cutting, the bearing case 28 is cut into the thrust ball bearing needle shape by the biasing force of the coil spring 34. The tapered portion 26b of the distal end surface 26a of the work clamp member 26, which protrudes slightly toward the distal end side of the distal end portion of the throw-away tip 21 of the tool body 20 via the roller bearing 29, comes into contact with the end portion of the workpiece 27, Next, the tip surface 26a comes into contact with the machined surface of the workpiece 27. At this point, the workpiece 27 is clamped under the biasing load of the workpiece clamp member 26, so chatter and vibration are suppressed, and normal cutting is performed. In this case, in order to prevent the thin wall portion of the workpiece 27 from deforming due to the biasing load applied to the workpiece 27 by the workpiece clamp member 26, the biasing load of the coil spring 34 is adjusted using the adjustment screw 32 in advance. It has been adjusted accordingly.

In addition, when removing the tool body 20 from the arbor 35 and replacing it, first loosen the clamp bolts 43 and clamp nuts 44 that are threaded together.
Both tapered parts 43 and 44a of the clamp nut 44
As a result, the cutter clamper 37, which has been pressed upward in FIG. As a result, the engagement between the tool body 20 and the clamp head 39, which had been firmly engaged until now, is loosened. Next, the tool body 20 is rotated 90° around its axis l with respect to the arbor 35,
The clamp head 39 is inserted into the mounting hole 40 of the tool body 20.
Match the long hole shape of the inlet. At this time, the key 41 of the arbor 35 moves smoothly along the arcuate keyway 42 of the tool body 20, so the rotation operation of the tool body 20 relative to the arbor 35 is performed smoothly. In addition, the clamp bolt 43
By loosening the clamp nut 44, the clamp bolt 43 moves outward in the mounting hole of the arbor 35, and the steel ball 45 pressed against the tapered portion 43b of the clamp bolt 43 moves downward in FIG. When the tool body 20 rotates 90 degrees and the shape of the clamp head 39 matches the elongated shape of the entrance of the mounting hole 40, the tool body 20 smoothly separates from the arbor 35. and removed.

Furthermore, when attaching the tool body 20 to the arbor 35, the above-mentioned procedure may be reversed.
That is, first, the clamp head 39 at the tip of the arbor 35 is inserted into the entrance of the mounting hole 40 of the tool body 20.
At the same time, the key 41 of the arbor 35 is fitted into the key groove 42 of the tool body 20.
Next, the tool body 20 is rotated 90 degrees and the clamp head 39 is rotated 90 degrees inside the mounting hole 40 to engage them. Then, by screwing the clamp bolt 43 into the clamp nut 44, the cutter clamper 37 is pulled toward the base end side of the arbor 35, and the clamp head 3
9 and the tool body 20 are firmly clamped together to complete the attachment of the tool body 20 to the arbor 35.

[Effect of idea]

As explained above, the present invention forms a recess at the center of the tip of the tool body, provides a support member in the recess so as to be movable along the axis of the tool body, and clamps the workpiece to the support member. The member is rotatably provided around the axis of the tool body, and the tool body is provided with biasing means for protruding the support member toward the distal end of the tool body, and the tool body is detachably attached to the arbor. Since the clamp mechanism to be attached is provided between the tool body and the arbor, it is possible to reliably suppress the occurrence of chatter and vibration in the workpiece and perform normal cutting, and also prevent chipping of the cutting edge. This has the excellent effect of not only preventing deterioration in machining accuracy but also allowing smooth attachment of the tool body to the arbor.

[Brief explanation of drawings]

Figures 1 to 3 show one embodiment of the present invention, with Figure 1 being a sectional view, Figure 2 being a bottom view, and Figure 3 being a bottom view.
The figures are - arrow direction views of Figure 1, Figures 4 to 6.
The figures show a conventional face milling cutter: Fig. 4 is a sectional view, Fig. 5 is a bottom view, and Fig. 6 is the same as Fig. 4.
It is a line arrow view. 20... Tool body, 25... Recess, 26... Work clamp member, 28... Bearing case (supporting member), 34... Coil spring (biasing means), 35...
Arbor, 36...clamp mechanism, l...axis line.

Claims (1)

[Scope of utility model registration request] A recess is formed in the center of the tip of the tool body, and a support member is provided in the recess so as to be movable along the axis of the tool body, and a work clamp member is mounted on the support member to rotate around the axis of the tool body. While it can be freely installed, the tool body has
A biasing means for protruding the support member toward the distal end of the tool body is provided, and a clamp mechanism for detachably attaching the tool body to the arbor is provided between the tool body and the arbor. Face milling cutter.