JPS61188045A - Vibrationproof damper for boring bar - Google Patents

Abstract

PURPOSE:To improve the vibration damping function by integrally constituting a holding member for holding a boring bar with the adhesive for adhesion-joint and using said adhesive as a vibrationproof damper. CONSTITUTION:A boring bar 3 is inserted into a penetration hole 2 formed onto a base holder 1, and screwed in the radial direction by three bolts 4A, 4B, and 4C, and said boring bar 3 is fastened onto the base holder 1. A flange 7 which has the smaller diameter than that of the base holder 1 and has the penetration hole 6 drilled for the insertion of the boring bar 3 is inserted at the top edge part of the base holder 1. Further, the adhesive 9 made of urethane- series high polymeric resin is applied onto the both or one of the rear edge parts of a holding member 7 consisting of the flange at the top edge part of the base holder 1, and the holding member 7 consisting of the flange is attached at the top edge part of the base holder 1, and screwed by a bolt 8, and the boring bar 3 is fastened.

Description

Detailed Description of the Invention (11) Field of Industrial Application The present invention relates to a damper for vibration isolation of a boring bar used by being attached to a base holder of a tool rest of a machine tool such as a turning machine machining center or a taper shank of a rotary tool. .

(2) Prior Art Conventionally, when a boring bar is attached to the base holder of the tool rest of a turning machine for machining, vibrations of the cutting edge etc. have been a cause of adverse effects on the finishing accuracy of the surface of the machined workpiece. Therefore, up until now, as anti-vibration suppression means to suppress the vibration of boring bars of machine tools, cutting grooves have been formed in the base holder that holds the tools of the boring bar bare, and elastic bodies etc. have been inserted in the joints to hold the tools. Means for fixing are known.

(3) Problems to be solved by the invention However, among the conventional anti-vibration suppression means, the former base holder is
The direction, width, depth, etc. of the cut groove to be made vary depending on the type of tool and cutting conditions, and it is difficult to maintain optimal conditions, so several types of holders are available depending on the type of machining. Must be replaced accordingly.

Furthermore, even in the latter case where an elastic body such as rubber is sandwiched, the elastic modulus changes or deteriorates after long-term use, forcing replacement, and adjustment is required each time.

(4) Purpose The purpose of the present invention was proposed in order to solve the problem in view of the above-mentioned circumstances. An object of the present invention is to provide a vibration-proof damper for a boring bar having vibration damping ability.

(5) Means and Effects for Solving the Problems In order to achieve the above object, the present invention applies an adhesive to the holding member that holds the boring bar either directly or through an intervening member at the tip of the base holder. The integrated structure is used as a vibration-proofing damper using the adhesive as an elastic body, and the vibration-proofing effect is obtained especially by shearing deformation applied to the adhesive part.

The adhesive used in the present invention may be any adhesive as long as it can bond metals together. For example, a viscous adhesive made of a polymeric resin such as acrylic or urethane is used.

Furthermore, the processing conditions such as temperature and time for bonding with an adhesive may be determined as appropriate and are not particularly limited.

(6) Examples Hereinafter, examples of the present invention will be described in detail based on the drawings.

<Example 1> A first embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a cross-sectional view showing the installed state of a boring bar to which a vibration-proofing damper of the present invention is attached. In Figure 1,
The boring bar 3 is inserted into the through hole 2 drilled in the base holder 1, and the three bolts 4A, 4B, and 4C are screwed together from the radial direction to fasten the boring bar 3 to the base holder 1. A tip 5 is attached to the tip of the boring bar 3, and a predetermined turning process is performed by movement of a tool rest to which the base holder 1 is attached. A flange 7 having a diameter slightly smaller than the diameter of the base holder 1 and having a through hole 6 formed for inserting the boring bar 3 is inserted into the tip of the base holder 1.

Furthermore, an adhesive 9 made of urethane-based polymer resin is applied in advance to one or both of the rear end portions of the holding member 7 consisting of the flange at the tip of the base holder 1, and then
A holding member 7 consisting of a flange is adhered to the tip of the base holder 1 and screwed together with a bolt 8 to fasten the boring bar 3.

By bonding the holding member 7 made of a flange to the tip of the base holder 1 with an adhesive 9, the vibration-proofing effect of the boring bar 3 is significantly exhibited.

In order to confirm the anti-vibration effect, (A) bolt 4A is shown in Figure 1.
, 4B and 4C are screwed together and tightened, (B)
In Fig. 1, when the two poles 1-4A and 4B are screwed together and tightened (pol 4C is removed), and as a conventional example, the anti-vibration damper of the present invention shown in Fig. 9 is not installed. The vibration state of the boring bar 3 was tested when it was used from the beginning.

That is, in (A) of the present invention, ([1), and the conventional example, a constant impact force is applied to the tip of the boring bar 3, and the vibration at that point in the X-axis direction is measured with a vibration meter. The results are shown in FIG. 6, FIG. 74, and FIG. 8, respectively. Note that the X-axis direction will be omitted since it is approximately the same as the X-axis direction.

In FIGS. 6 to 8, the horizontal axis represents frequency and the vertical axis represents amplitude. FIG. 6 shows (A) of the present invention, and FIG. 7 shows (A) of the present invention.
B) and FIG. 8 are conventional examples, and the maximum apex on each vertical axis is the resonance point 0.

Comparing the frequency and amplitude at this resonance point, it is clear from the figure, but when tabulated together with the attenuation rate, the following table shows the results.

As shown in the table, (^) and (rl) of the present invention showed significant differences in amplitude and damping rate compared to the conventional example, and exhibited effects.

<Example 2> A second embodiment of the present invention will be described with reference to FIG.

FIG. 2(A) is a cross-sectional view showing the installed state of the boring bar to which the vibration-proofing damper of the present invention is attached, similar to FIG. 1. As shown in FIGS. 2(a) and 2(o), a shaft portion 7B is integrally formed with a flange portion 7A of a holding member 7 provided with a through hole 6 for inserting the boring bar 3 in the central axis direction. is inserted into the through hole 2 formed in the base holder 1.

Further, an adhesive 9 is applied to the front surface of the flange 7, and an adapter 10 having a tapered conical through hole 12 in the center is adhered thereto. Next, bolt 4 from the radial direction of base holder 1.
Tighten the shaft portion 7B of the flange 7 with A, 4B and 4C. A portion of the taper of a quarter core (11) having a through hole in the center into which a boring bar is inserted and formed at one end of the flange 13 is engaged with the conical through hole 12 of the adapter 10, and the bolt 14 is inserted. When the adapter 10 is evenly tightened and fixed, the boring bar 3 is also clamped by the collet. Furthermore, the boring bar 3 is tightened with bolts 8 from the radial direction of the flange 7.

Even the vibration-proofing damper having the structure shown in FIG. 2 has a vibration-proofing effect comparable to or greater than that of the damper shown in FIG.

<Embodiment 3> A third embodiment of the present invention will be described with reference to FIGS. 3 and 4.

Similar to FIGS. 1 and 2, FIG. 3 is a cross-sectional view showing the installed state of the boring bar to which the vibration-proofing damper of the present invention is attached, and FIG. 4 is a view taken in the direction of arrow II in FIG. 3.

In FIGS. 3 and 4, a boring bar 3 with a tip 5 attached to its tip is inserted into a through hole 2 formed in a base holder 1. A flange 7 having a through hole 6 formed for inserting a boring bar 3 is fixed to the tip of the base holder 1 with a bolt 15.

Furthermore, an adhesive 9 is applied to the front surface of the flange 7, and an adapter 10 having a conical through hole 11a in the center is adhered thereto.

A tapered portion 16a of a collet 16 is engaged with the conical hole 11a of the adapter 10, which has a through hole in the center into which the boring bar 3 is inserted and has a threaded portion 16b at one end.

Next, with the boring bar 3 inserted into the collet 16, the nut 17 screwed into the threaded portion 16b of the collet is turned, and the boring bar 3 is rotated by the action of the collet.
to clamp.

Next, after positioning the cutting edge of the boring bar 3,
By tightening the clamp bolts Y+ and Yt on the side of the slotted portion X□ formed in the base holder, the shank portion of the boring bar 9 is firmly fixed.

In the anti-vibration damper having such a structure, the diameter of the boring bar 3 is D, and the length from the tip of the base holder 1 to the tip of the boring bar 3 is L. Furthermore, the length from the tip of the nut 17 to the tip of the boring bar 3 is assumed to be l.

Therefore, cutting speed 100 m/lll1n, depth of cut l
When machining was performed under the machining conditions of lll11 and a feed rate of 0.1 arm/rev, the vibration state was improved from the normal limit of 5 for the value of 1/D to 7. That is, l/
The improvement in the value of D from 5 to 7 was recognized as an effect of the anti-vibration damper of the present invention.

<Example 4> A fourth embodiment of the present invention will be described with reference to FIG.

FIG. 5 is a side view showing a partial cross section of a boring bar integrally formed with a shank used in a machine tool such as a machining center.

In FIG. 5, the shank portion 21a of the boring bar 22 is inserted into the main shaft 20. A boring bar 22 is integrally formed at the center of the tip of the grip part 21 provided on the shank part 21a. A tip 5 is attached to the tip of the boring bar 22.

Further, an annular groove 21b is provided at the boundary between the shank 21a and the boring bar integrally formed to protrude from the gripping portion 21.
is drilled.

Adhesive 26 is uniformly applied to both or one side of the front end of the tool gripping portion 21 and the rear end surface of the flange 24 and bonded to each other. Furthermore, the boring bar 22 is fixed from the radial direction of the flange 24 with bolts 25 or adhesive.

In the case of this embodiment, there is a resonance effect when force is applied in the shearing direction, and the effect is exhibited for such use.

Furthermore, the tool holder equipped with the vibration-proofing damper of the present invention can be effectively used as a replacement tool.

(7) Effects The present invention provides a vibration-proofing damper in which the base holder is clamped by a holding member such as a flange that holds the boring bar at the tip of the base holder, and then glued and integrated, using the adhesive as an elastic body.
In particular, since the vibration damping effect is achieved through shear deformation of the adhesive portion, the structure is simple, and the vibration damping ability is improved and more effective than in the past.

The tool with anti-vibration damper of the present invention can be used in turning machine tools or machining centers, and can also be used as a replacement tool.

[Brief explanation of drawings]

Figures 1, 2 (a) and 3 are cross-sectional views of each embodiment showing the installed state of the boring bar to which the vibration isolating damper of the present invention is attached, and Figure 2 (Il+) is a cross-sectional view of each embodiment. Figure 2 (
B) is a view taken along the line G-G, and Figure 4 is the same as Figure 3! 7I is a view taken along arrow 7I. FIG. 5 is a side view of a boring bar showing a partial cross section of the fourth embodiment. 6-7 are frequency characteristic diagrams showing the relationship between frequency and amplitude tested with the present invention, and FIG. 8 is a frequency characteristic diagram showing the relationship between frequency and amplitude tested with the conventional type. FIG. 9 is a sectional view showing a conventional boring bar installation state. 1...Base holder 2.23...Through hole 3.2
2... Boring bar 4A, 4B, 4C... Bolt 5... Chip 6... Through hole 7.24.
...Flange 8...Bolt 9.26...Adhesive 11...Collet 13...Naft
21... Tool holder patent applicant Director of the Agency of Industrial Science and Technology Ministry of International Trade and Industry Figure 1 Figure 2 (a)

Claims (1)

[Claims] A boring bar characterized in that it has an integrated structure with an adhesive that adhesively bonds a holding member that holds the boring bar to the tip surface of the base holder directly or through an intervening member, and the adhesive serves as a vibration-proofing damper. anti-vibration damper