JPH0623672A - Noise suppression structure of diamond cutting grinding wheel - Google Patents

Abstract

PURPOSE:To provide the base sheet structure of a diamond cutting grinding wheel which has excellent noise suppression effect without lowering a base sheet strength. CONSTITUTION:In the noise suppression structure of a diamond cutting grinding wheel formed such that diamond segment chips are fixed on the outer periphery of a disc-shaped base sheet, a plurality of slits 3 for absorbing vibration approximately in a Z-shape each comprising a linear auxiliary line 3a and base lines 3b and 3c extended in the reverse direction to each other from the upper and lower ends of the auxiliary line 3a are arranged such that the auxiliary lines 3a of the slits 3 for absorbing vibration are positioned in the radial direction of the base sheet 1 and a central position for the auxiliary lines 3a is positioned on a concentric circle to the base sheet 1 to form a vibration absorbing part. A plurality of the absorbing parts are formed on the base sheet 1 on the basis of concentric circles R2 and R3 having a radius different from that of the concentric circle R1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to stone, concrete,
The present invention relates to a noise suppressing structure of a diamond cutting grindstone used for cutting refractories and the like.

[0002]

2. Description of the Related Art Conventionally, as such a diamond cutting grindstone, one in which a diamond segment chip is fixed to the outer circumference of a disk-shaped substrate made of iron or stainless has been widely used.

This cutting grindstone is attached to a predetermined machine and can be rotated at a high speed to bring a segment tip into contact with a work material and cut into an arbitrary shape by a rotational force.

One of the problems with such a diamond cutting grindstone is noise and vibration generated during use.

There are various possible causes for the noise generated during the work. One is caused by the turbulent flow due to the high speed rotation of the segment tip provided in the peripheral portion of the rotating substrate, and the other when the work material collides with the segment tip. It is conceivable that the vibrations due to these external forces resonate with the disk-shaped rotating substrate to generate a loud sound.

Various attempts have hitherto been made to reduce such noises, for example, in the actual development of Sho 58-.
Japanese Patent Publication No. 70869 discloses a substrate structure in which a plurality of substrates having different natural frequencies are laminated and integrated by spot welding. As a result, the number of resonance points can be reduced, and the resonance prevention effect is exhibited.

However, since this substrate structure is integrated by spot welding, the bending strength of the substrate is small, the processing accuracy is poor, and further, the rigidity of the substrate is low, so that runout easily occurs during rotation. However, there are problems such as high manufacturing cost.

As a solution to this problem, for example, Japanese Patent Publication No. 4-13100 and Japanese Patent Publication No. 4-131.
No. 01 publication proposes a substrate structure in which a slit having a predetermined shape is formed on a rotating substrate, and the slit is filled with a vibration absorbing resin. By providing such a vibration absorbing slit, it is possible to partially block the propagation of noise generated during the work in the rotating substrate, and to some extent prevent the generation of noise due to resonance of the rotating substrate.

[0009]

By the way, the resonance motion of the rotating substrate is composed of a flexing motion having a node in the diameter direction (node diameter) and an axial motion having a circle around the rotation axis as a node (node circle). The magnitude of the vibration amplitude is minimum or zero at the node position, and the amplitude becomes maximum as the distance from the node increases, that is, at the intermediate position between the nodes and the outer peripheral position.

When actually examining the vibration mode at the resonance frequency of the diamond cutting wheel, most of the vibration modes have a node circle. That is, there are alternately concentrically vibrating portions (vibration antinodes) and non-vibrating portions (vibration nodes).

Therefore, in order to control the noise during the cutting of the diamond cutting grindstone, the main component of the noise is 2 to 7 KH.
It can be said that, in the vibration modes at a plurality of resonance points existing in z, it is most effective to form the concentric control parts in the antinode part of the vibration.

However, the slit structures disclosed in Japanese Patent Publication No. 4-13100 and Japanese Patent Publication No. 4-13101 are basically arcuate structures, and the slits cannot be elongated concentrically. It is not possible to form many damping parts in the antinode portion of the existing vibration, and it is not possible to dampen all of a plurality of resonance points. Therefore, it is difficult to sufficiently exert the noise reduction effect.

An object to be solved by the present invention is to obtain a substrate structure of a diamond cutting grindstone excellent in noise suppressing effect without lowering the substrate strength.

[0014]

In order to solve the above problems, the present invention provides a noise suppressing structure for a diamond cutting grindstone in which a diamond segment tip is fixed to the outer periphery of a disk-shaped substrate, and a linear auxiliary wire and A substantially Z-shaped vibration-absorbing slit consisting of base lines extending in opposite directions from the upper and lower ends of the auxiliary line, the auxiliary line of the vibration-absorbing slit being located in the radial direction of the substrate, and concentric with the substrate. A plurality of vibration absorbing parts are formed so that the center position of the auxiliary line is aligned,
In addition, a plurality of the same vibration absorbing portions are formed on the substrate with reference to a concentric circle having a radius different from that of the concentric circle.

Here, the position of the base line is arranged so as to be located at a nodal circle of the disk-shaped substrate and an intermediate part of the nodal circle or a part close thereto, and the auxiliary line is at an intermediate position of the nodal diameter and the nodal diameter. To arrange.

[0016]

In the present invention, the base line of the vibration absorbing slit formed in the circumferential direction of the disk-shaped substrate prevents propagation of vibration in the axial direction of the circle around the rotation axis as a node and is formed in the radial direction. The auxiliary line of the vibration absorbing slit suppresses flexural vibration having nodes in the diametrical direction. Further, by forming a plurality of the vibration absorbing parts on different radii, it is possible to suppress a plurality of different resonance points.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A noise suppressing structure for a diamond cutting grindstone of the present invention will be specifically described below with reference to an embodiment shown in the drawings.

FIG. 1 is a front view of a diamond cutting whetstone having a noise suppressing structure of this embodiment.

In the figure, reference numeral 1 is a disk-shaped substrate having a mounting hole 1a formed in the center thereof, and a diamond segment chip 2 is fixed to the outer peripheral portion of the substrate 1.

3 is a part of the substrate 1 with a laser of 0.3 mm
With the vibration absorbing slits cut in a straight line, a linear auxiliary line 3a and a base line 3 extending in opposite directions from the upper and lower ends of the auxiliary line 3a.
It is formed in a substantially Z shape composed of b and 3c. The slit 3 is filled with an ultraviolet curable resin and has a wavelength of 550 nm.
UV light is applied for 3 seconds to cure.

The vibration absorbing slit 3 is arranged so that the auxiliary line 3a is aligned with the radial direction of the substrate 1, and is formed concentrically with the substrate ₁ on the first circumference D ₁ having a radius R ₁ and It is formed so that the center position of the auxiliary line 3a is located. In this embodiment, six vibration absorbing slits 3 were formed on the first circumference D ₁ and used as the first vibration absorbing portion.

[0022] Further, on the second circle D ₂ of radius R _2, also form the third circumferential D likewise six increments ₃ on each vibration absorbing slit 3 having a radius R _3, the second vibration absorbing Part and the third vibration absorbing part.

Next, the positional relationship between the installation of the first, second and third vibration absorbing parts and the node circle will be described.

In obtaining the diamond cutting grindstone of this embodiment, a diamond cutting grindstone having the same shape without forming a vibration absorbing slit was used, and vibration was applied in the range of 2 to 7 KHz, which is the main component of noise, to F ₁ = 3800 Hz, F. ₂ = 5200
A resonance frequency of Hz, F ₃ = 6900 Hz was obtained.

FIGS. 2A, 2B and 2C show vibration modes at the respective resonance frequencies.

Explaining FIG. 2 (a) as an example, three points X _{11 to} X ₁₃ intersecting the center line of the figure become nodes of vibration, and the peaks of the vibration mode shown as points Y _{11 to} Y ₁₄ are shown. The valley is the antinode of vibration. The numbers shown in the upper part of FIG. 2A indicate the distances from the center of the substrate to the respective antinodes Y _{12 to} Y ₁₄ .

Here, the first circumference D ₁ of radius R ₁ formed at the outermost peripheral portion shown in FIG. ₁ is from the center of f ₁ = 3800 Hz to the third antinode Y ₁₃ in FIG. 2A. Distance of 202mm and distance 242m to the fourth belly Y ₁₄
The average value of m is 222 mm. That is, the base line 3b is fourth belly Y ₁₄ vibration absorbing slit 3, so that the base line 3c are respectively positioned at the third abdominal Y _13.

Further second circumferential D ₂ of radius R ₂ Similarly,
In FIG. 2B, 5 from the center of f ₂ = 5200 Hz
The average value of the distance to the second antinode Y ₂₅ and the distance to the fourth antinode Y ₂₄ is 202 mm, and the baseline 3 b of the vibration absorbing slit 3
Is located at the fifth antinode Y ₂₅ , and the base line 3c is located at the fourth antinode Y ₂₄ .

Further the third circumferential D ₃ of radius R ₃ Similarly,
In FIG. 2C, 5 from the center of f ₃ = 6950 Hz
The average value of the distance to the fourth antinode Y ₃₅ and the distance to the fourth antinode Y ₃₄ is 182 mm, and the base line 3 b of the vibration absorbing slit 3
Is located on the fifth antinode Y ₃₅ , and the baseline 3c is located on the fourth antinode Y ₃₄ .

As described above, in this embodiment, the base lines 3b _and 3c of the vibration-absorbing slit 3 are arranged in a stepwise manner at the portions located on the peculiar antinodes of the substrate corresponding to the respective resonance frequencies measured in advance. Therefore, it is possible to prevent the resonance frequency from propagating in the range that causes noise and effectively suppress the generation of noise due to resonance. Further, by the action of the auxiliary line 3a of the vibration absorbing slit 3 formed in the radial direction of the substrate, it is possible to simultaneously prevent the propagation of the flexural vibration having the node in the radial direction. Further, by the action of the ultraviolet curable resin filled in the slit, the vibration damping effect can be enhanced, and the strength reduction of the substrate 1 due to the formation of the vibration absorbing slit 3 can be compensated.

[Test Example 1] Next, in order to confirm the effect of this embodiment, noise and the like were actually used. As Comparative Example 1, a diamond cutting grindstone made of a normal substrate was used.
As Comparative Example 2, a diamond cutting grindstone having a substrate structure having a semicircular slit described in Japanese Patent Publication No. 4-13101 was used.

All of these are varieties: EV50, outer diameter: 5
60 mm, segment length: 40 mm, segment thickness 3.5 mm, segment height: 8.0 mm, substrate thickness:
2.8 mm, slit width: 2 mm, slit depth: 17
mm, hole diameter: φ6 mm was used.

The cutting conditions are shown in Table 1.

[0034]

[Table 1] Under the above cutting conditions, a JEIC normal sound level meter type 1015 was installed at a position 1 m away from the substrate, and the noise during cutting was measured.

As a result, FIG. 3 shows a noise spectrum analysis diagram in FIG.

As is clear from the figure, in this example, the noise suppressing effect was clearly confirmed as compared with Comparative Examples 1 and 2.

[Test Example 2] Further, in order to confirm the strength of the substrate itself, a load of 7 kg was horizontally applied to a position 30 mm from the outer peripheral portion of the segment grindstone to measure the bending strength of the substrate.

As Comparative Example 1, a diamond cutting grindstone made of a normal substrate was used, and as Comparative Example 2, Japanese Patent Publication No. 4-131.
The diamond cutting whetstone of the substrate structure having the semicircular slits described in JP-A No. 01-101 was used, and the diamond cutting whetstone of the composite substrate described in JP-A-58-70869 was used as Comparative Example 3.

As shown in FIG. 5, the substrate bending strength index of 98 of this example is 100, that of Comparative example 1 is 94, that of Comparative example 2 is 94, and that of Comparative example 3 is 88. The strength substantially equal to that of Comparative Example 1 in which the slit was not formed was secured.

[0040]

According to the present invention, the following effects can be obtained.

(1) Propagation of the resonance frequency in the range that causes noise can be prevented, and noise generation due to resonance can be effectively suppressed.

(2) The bending strength of the substrate is high, and the processing accuracy can be maintained.

[Brief description of drawings]

FIG. 1 is a front view of a diamond cutting whetstone provided with a noise suppressing structure of the present embodiment.

FIG. 2 is a graph showing a vibration mode at each resonance frequency.

FIG. 3 is a graph showing noise measurement results.

FIG. 4 is a graph showing a noise spectrum analysis result.

FIG. 5 is a graph showing bending strength of a substrate.

[Explanation of symbols]

1 substrate 2 diamond segment tip 3 vibration absorption slit 3a auxiliary lines 3b, 3c baseline X _{11 to} X ₃₆ vibration node Y _{11 to} Y ₃₇ vibration antinode

Claims (1)

[Claims] 1. A noise suppressing structure for a diamond cutting grindstone in which a diamond segment tip is fixed to the outer periphery of a disk-shaped substrate, wherein a straight auxiliary line and base lines extending in opposite directions from the upper and lower ends of the auxiliary line. A plurality of substantially Z-shaped vibration absorbing slits are arranged so that the auxiliary line of the vibration absorbing slit is located in the radial direction of the substrate and the center of the auxiliary line is concentric with the substrate. A noise suppressing structure for a diamond cutting grindstone, characterized in that a plurality of parts are formed and a plurality of the same vibration absorbing parts are formed on the substrate with reference to a concentric circle having a radius different from the concentric circle.