JPS6333019B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vibration-isolating shaft member used for vibration-isolating tools, rotating shafts, and the like.

Prior Art A shaft member with a relatively long shaft portion that supports the base side and applies an excitation force to the tip side, such as a shaft member such as a boring tool or a grinding wheel arbor, has a ratio of length to diameter. It is necessary to construct the material in a long shape with a large diameter, and as a result, chatter vibration occurs during machining, reducing machining accuracy and, depending on the machining conditions, machining may become difficult.

Various proposals have been made to solve the above-mentioned difficulties, but no means have been found that easily and effectively provide vibration isolation, and it has not been possible to easily achieve vibration isolation without directionality.

Problems to be Solved by the Invention The present invention enables high vibration damping performance to be obtained over a wide vibration range without any adjustment using simple means, and also allows for easy realization of non-directional vibration isolation. The present invention attempts to propose a vibration-isolating shaft member having the following structure.

Means for Solving the Problems In order to achieve the above object, the vibration isolating shaft member of the present invention is a shaft member that supports the base side and suppresses the vibration of the shaft portion on which the excitation force is applied to the distal end side. The shaft part is constructed by inserting a core material into the inside of a shell made of a tube material through a viscous material for vibration absorption, and the core material is formed by a plurality of core materials in a plane along the axis of the core material. It is constructed by dividing it into constituent pieces and joining these constituent pieces via a viscous material placed between the cut surfaces.

Functions and Effects In the vibration-isolating shaft member configured as described above, when an excitation force is applied to the tip, the vibration between the shell in the shaft and the core material inserted into the shell, and between the plurality of core materials constituting the core material A large shear deformation occurs in the viscous material between the core components of the core material and absorbs the vibration energy, so unlike vibration isolation by dispersing the resonance points by changing the spring constant, the vibration can be applied over a wide vibration range without adjustment. High damping capacity can be obtained and effective vibration isolation can be achieved.

Examples Examples of the present invention will be described in detail below with reference to the drawings.

1 and 2 show an embodiment in which the present invention is applied to a boring tool, in which a mounting base 1, a blade part 2
and a shaft portion 3 that connects them.

The shaft part 3 whose one end is fixed to the above-mentioned mounting base 1 is
A substantially cylindrical core material is fitted into a shell body 11 made of a tube material made of a material having high rigidity, and a viscous material 6 made of acrylic resin or the like for absorbing vibrations is inserted and fixed therein. 12, and the core material 12 is formed by dividing a cylindrical member made of a highly rigid material like the shell body 11 into four equal parts along two orthogonal planes along its axis, and forming four core material constituent pieces 13. The component pieces 13 are integrally connected in a cylindrical shape using the same viscous material 7 as described above disposed between the cut surfaces.

Further, at the tip of the shaft portion 3, a shell body 11
is formed to be longer than the core material 12, and a blade attachment hole 14 is formed at the end of the shaft portion 3, and a support member 16 for the cutting edge 17 of the blade portion 2 is fitted and fixed into the attachment hole 14.

The above-mentioned mounting base 1, blade part 2, and core material 12 are:
If necessary, the same viscous material as above can be interposed between them and they can be opposed to each other without being fixedly connected.

As each of the above-mentioned viscous materials, various materials having desired viscosity can be used, and the above-mentioned core material 1
2 does not necessarily have to divide it into four equal parts, but 2
In the case of equal division, directionality will occur in the vibration isolation, and in order to perform vibration isolation without directionality, it is necessary to divide it into at least three equal divisions.

Various methods can be used to assemble the shaft portion 3 in the above-mentioned tool, but for example, the core material 12 is constructed by integrating four core material constituent pieces 13 with the viscous material 7, and the core material 12 is A viscous material 6 is applied to the outer peripheral surface, and the core material 12 is inserted into the shell 11 using the adhesive applied to the inner surface of the shell 11 as a lubricant, and as the adhesive hardens, the viscous material is applied inside the shell. It is also possible to adopt a method of inserting the core material through the core material.

When a workpiece is cut using a boring tool configured as described above, an excitation force that causes chatter vibration is applied to the boring tool, but the vibration is
Due to the action of the core material provided inside the tool to increase the vibration damping ability, energy is absorbed by generating large strains in the viscous material at various parts, thereby preventing vibration of the boring tool.

FIG. 3 shows a shank cross section when applied to a square shank used for turning or the like.
In this case, the overall structure of the tool will be similar to that shown in FIG. Therefore, the same reference numerals are given to the same or corresponding parts as in the above embodiment, and the explanation thereof will be omitted.

FIGS. 4 to 7 are diagrams showing the results of experiments conducted to confirm the effects of the present invention.

In these experimental examples, a conventional tool having an integral shaft portion was used as the tool 1, and the wall thickness of the shell in the embodiment of the present invention was 1.5 mm and 1.0 mm.
mm tools were designated as tool 2 and tool 3. Figure 4~
Figure 7 shows the measurement of the vibration damping state of tools 1 to 3 when an external impact is applied to them. The vibrations disappeared much more quickly than in Tool 1 (FIG. 4).

Furthermore, Fig. 7 shows the stable range where chatter vibration does not occur and the unstable range where chatter vibration occurs under various machining conditions using tools 1 to 3. From the figure, it can be seen that the tools 2 and 3 of the present invention are more stable at high cutting speeds than the conventional tool 1 at the same feed rate, and among the tools 2 and 3 of the present invention, the thickness of the shell body is It can be seen that the thinner tool 3 is more stable.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line A--A, FIG. 3 is a sectional view of another embodiment at the same position as FIG. 4, and FIG. ~7th
The figure is a diagram showing experimental results for confirming the effects of the present invention. 2... Blade part, 3... Shaft part, 6, 7... Viscous material, 11
...Shell body, 12... Heartwood, 13... Heartwood component piece.

Claims (1)

[Claims] 1. A shaft member that supports the base side and suppresses vibrations of the shaft portion on which an excitation force is applied to the distal end side,
The shaft portion is constructed by inserting a core material into a shell made of a tube material through a viscous material for vibration absorption, and the core material is divided into a plurality of core component pieces on a plane along the axis thereof. A vibration-isolating shaft member characterized in that these constituent pieces are connected via a viscous material disposed between the cut surfaces.